Purpose:The article investigates how to make a broader understanding of sustainability relevant for early childhood education(ECE)guided by the four dimensions suggested by United Nations Educational,Scientific and Cu...Purpose:The article investigates how to make a broader understanding of sustainability relevant for early childhood education(ECE)guided by the four dimensions suggested by United Nations Educational,Scientific and Cultural Organization:ecological,economic and social/cultural sustainability,and good governance.Design/Approach/Methods:Previous research on ECE on sustainability is discussed in relation to the four dimensions and to Biesta’s concepts of socialization,qualification,and subjectification.Findings:The investigation finds that all four dimensions are necessary in ECE for sustainability,and it suggests how the dimensions can be understood,how they may overlap,and how they can be contradictive.Originality/Value:The article depicts how children’s opportunities to engage and to disturb established ways of thinking can be facilitated through all dimensions.展开更多
The aggregation of multi-walled carbon nanotubes （MWCNTs） in the aqueous phase not only inhibits their extensive utilization in various aspects but also dominates their environmental fate and transport.The role of s...The aggregation of multi-walled carbon nanotubes （MWCNTs） in the aqueous phase not only inhibits their extensive utilization in various aspects but also dominates their environmental fate and transport.The role of surfactants at low concentration in the aggregation of MWCNTs has been studied,however the effect of perfluorinated surfactants at low concentration is uncertain.To understand this interfacial phenomenon,the influences of perfluorooctanoic acid （PFOA）,and sodium dodecyl sulfate （SDS） as a control,on MWCNT aggregation in the aqueous phase were examined by the UV absorbency method.Influences of pH and cationic species on the critical coagulation concentration （CCC） value were evaluated.The CCC values were dependent on the concentration of PFOA,however a pronounced effect of SDS concentration on the CCC values was not observed.The CCC values of the MWCNTs were 51.6 mmol/L in NaCl and 0.28 mmol/L in CaCl 2 solutions,which suggested pronounced differences in the effects of Na＋ and Ca2＋ ions on the aggregation of the MWCNTs.The presence of both PFOA and SDS significantly decreased the CCC values of the MWCNTs in NaCl solution.The aggregation of the MWCNTs took place under acidic conditions and was not notably altered under neutral and alkaline conditions due to the electrostatic repulsion of deprotonated functional groups on the surface of the MWCNTs.展开更多
文摘Purpose:The article investigates how to make a broader understanding of sustainability relevant for early childhood education(ECE)guided by the four dimensions suggested by United Nations Educational,Scientific and Cultural Organization:ecological,economic and social/cultural sustainability,and good governance.Design/Approach/Methods:Previous research on ECE on sustainability is discussed in relation to the four dimensions and to Biesta’s concepts of socialization,qualification,and subjectification.Findings:The investigation finds that all four dimensions are necessary in ECE for sustainability,and it suggests how the dimensions can be understood,how they may overlap,and how they can be contradictive.Originality/Value:The article depicts how children’s opportunities to engage and to disturb established ways of thinking can be facilitated through all dimensions.
基金supported by the National Natural Science Foundation of China(No.20977043,20777033)the Opening Funding of State Key Laboratory of Pollution Control and Resource Reuse(No.PCRRF12012)
文摘The aggregation of multi-walled carbon nanotubes （MWCNTs） in the aqueous phase not only inhibits their extensive utilization in various aspects but also dominates their environmental fate and transport.The role of surfactants at low concentration in the aggregation of MWCNTs has been studied,however the effect of perfluorinated surfactants at low concentration is uncertain.To understand this interfacial phenomenon,the influences of perfluorooctanoic acid （PFOA）,and sodium dodecyl sulfate （SDS） as a control,on MWCNT aggregation in the aqueous phase were examined by the UV absorbency method.Influences of pH and cationic species on the critical coagulation concentration （CCC） value were evaluated.The CCC values were dependent on the concentration of PFOA,however a pronounced effect of SDS concentration on the CCC values was not observed.The CCC values of the MWCNTs were 51.6 mmol/L in NaCl and 0.28 mmol/L in CaCl 2 solutions,which suggested pronounced differences in the effects of Na＋ and Ca2＋ ions on the aggregation of the MWCNTs.The presence of both PFOA and SDS significantly decreased the CCC values of the MWCNTs in NaCl solution.The aggregation of the MWCNTs took place under acidic conditions and was not notably altered under neutral and alkaline conditions due to the electrostatic repulsion of deprotonated functional groups on the surface of the MWCNTs.
