We investigate the effects of extension and overlap of wavefunctions on the dispersion relations of plasmon modes in symmetric double-quantum-well structures. We compare the approximate results in two-dimensional laye...We investigate the effects of extension and overlap of wavefunctions on the dispersion relations of plasmon modes in symmetric double-quantum-well structures. We compare the approximate results in two-dimensional layer-gas (2DLG) model with the exact ones where the extension and overlap of the wavefunctions are included. Our numerical results show that the 2DLG model is a good approximation only in the wide barrier case in the long wavelength limit. When the barrier is thin, the extension and overlap of the wavefunctions cannot be neglected. We also show that the long wavelength gap of the inter-subband mode is proportional to the energy difference between the ground and the first excited energy levels.展开更多
L-threonine(L-Thr) obtained by fermentation often contains vestigial hydrosoluble Pb(Ⅱ), Fe(Ⅱ), L-glutamic acid(L-Glu) etc., which affect the product quality. Poly melamine and L-aspartic acid(L-Asp) resin functiona...L-threonine(L-Thr) obtained by fermentation often contains vestigial hydrosoluble Pb(Ⅱ), Fe(Ⅱ), L-glutamic acid(L-Glu) etc., which affect the product quality. Poly melamine and L-aspartic acid(L-Asp) resin functional coconut shell activated carbon composite(PMA/AC) was prepared by a pressure relief-dipping-microwave assisted polymerization method for the simultaneous removals. The adsorption capacities of Pb(Ⅱ), Fe(Ⅱ) and L-Glu could reach to 82.34 mg·g^(-1), 57.82 mg·g^(-1) and 102.58 mg·g^(-1) at conditions of pH 5.0, 45 °C and 4 h with an initial concentration of 0.01 mol·L^(-1), respectively. The present PMA/AC was successfully used to the simultaneous removals of vestigial Pb(Ⅱ), Fe(Ⅱ) and L-Glu from the fermented crude product solution of L-Thr. Moreover, the PMA/AC was carefully characterized by FE-SEM, IR et al. analysis techniques, the results show that abundant PMA particles evenly distributed at the inner and outside surface of AC with a size of(50 ± 20) nm.展开更多
Wet granulation is a potential method to develop artificial aggregates.In this paper,the granulation of recycled alkali-activated slag powders with different particle size(d_(50) ranging between 12.9-127.7μm)distribu...Wet granulation is a potential method to develop artificial aggregates.In this paper,the granulation of recycled alkali-activated slag powders with different particle size(d_(50) ranging between 12.9-127.7μm)distributions were investigated in order to find how these affect on the engineering properties of the artificial aggregates.Blast furnace slag was added as co-binder in 10-30 wt.%during the granulation process and to enhance the properties,especially mechanical strength.The results show that the particle size of the raw material significantly affects the engineering properties of the produced aggregates,such as the crushing force(19-131.8 N),bulk density,water absorption,porosity and microstructure of the granules.The results show that granulation is a promising method to recycle alkali-activated materials as lightweight aggregates to replace natural aggregates.展开更多
The physical-mechanical,chemical,and durability characteristics of alkali-activated materials(AAMs)have been widely investigated.However,a critical gap in the literature is the lack of a comprehensive overview of rece...The physical-mechanical,chemical,and durability characteristics of alkali-activated materials(AAMs)have been widely investigated.However,a critical gap in the literature is the lack of a comprehensive overview of recently published literature regarding the life cycle assessment(LCA)of these binders.This study aims to fill that gap by conducting a systematic literature review of globally published literature on the topic.This paper consolidates knowledge by searching different databases,focusing on LCA studies that used AAMs as pastes,mortars,concretes,bricks,and rammed earth/soil blocks.The selected articles were reviewed and categorized based on precursors,alkaline activators,functional units,system boundaries,life cycle inventory databases,allocation,impact methodologies,and software used.Additionally,this paper also critically analyzes the key challenges of LCA for AAMs.The major challenges were identified as selecting a functional unit,subjectivity in boundary systems,and data interpretation.This work concludes that AAMs show substantial advantages in global warming potential compared to ordinary Portland cement-based materials;however,the average of other categories such as marine ecotoxicity and ozone layer depletion has been reported to be higher than for the reference samples.展开更多
文摘We investigate the effects of extension and overlap of wavefunctions on the dispersion relations of plasmon modes in symmetric double-quantum-well structures. We compare the approximate results in two-dimensional layer-gas (2DLG) model with the exact ones where the extension and overlap of the wavefunctions are included. Our numerical results show that the 2DLG model is a good approximation only in the wide barrier case in the long wavelength limit. When the barrier is thin, the extension and overlap of the wavefunctions cannot be neglected. We also show that the long wavelength gap of the inter-subband mode is proportional to the energy difference between the ground and the first excited energy levels.
基金Supported by the National Natural Science Foundation of China(U1407110)2014 Special Funds of Guangdong Province for Collaborative Innovation and Environment Platform Construction,Public Research and Capacity Building(2014B090901010)
文摘L-threonine(L-Thr) obtained by fermentation often contains vestigial hydrosoluble Pb(Ⅱ), Fe(Ⅱ), L-glutamic acid(L-Glu) etc., which affect the product quality. Poly melamine and L-aspartic acid(L-Asp) resin functional coconut shell activated carbon composite(PMA/AC) was prepared by a pressure relief-dipping-microwave assisted polymerization method for the simultaneous removals. The adsorption capacities of Pb(Ⅱ), Fe(Ⅱ) and L-Glu could reach to 82.34 mg·g^(-1), 57.82 mg·g^(-1) and 102.58 mg·g^(-1) at conditions of pH 5.0, 45 °C and 4 h with an initial concentration of 0.01 mol·L^(-1), respectively. The present PMA/AC was successfully used to the simultaneous removals of vestigial Pb(Ⅱ), Fe(Ⅱ) and L-Glu from the fermented crude product solution of L-Thr. Moreover, the PMA/AC was carefully characterized by FE-SEM, IR et al. analysis techniques, the results show that abundant PMA particles evenly distributed at the inner and outside surface of AC with a size of(50 ± 20) nm.
基金support received for the project DeConcrete Eco-Efficient Arctic technologies cooperation funded by kolarctic CBC initiative of European Union(KO 4068).XRD analysis was performed at the Center of Microscopy and Nanotechnology(University of Oulu).The authors would like to thank Jarno Karvonen and Elisa Wirkkala for their assistance with the laboratory experiments.
文摘Wet granulation is a potential method to develop artificial aggregates.In this paper,the granulation of recycled alkali-activated slag powders with different particle size(d_(50) ranging between 12.9-127.7μm)distributions were investigated in order to find how these affect on the engineering properties of the artificial aggregates.Blast furnace slag was added as co-binder in 10-30 wt.%during the granulation process and to enhance the properties,especially mechanical strength.The results show that the particle size of the raw material significantly affects the engineering properties of the produced aggregates,such as the crushing force(19-131.8 N),bulk density,water absorption,porosity and microstructure of the granules.The results show that granulation is a promising method to recycle alkali-activated materials as lightweight aggregates to replace natural aggregates.
基金supported by the Alexander von Humboldt Foundation,International Climate Protection Fellowship(Ref 3.5—1157991-IRN-IKS)This financial support is gratefully appreciated by Morteza Nikravan.Rafia Firdous and Dietmar Stephan highly acknowledge Bundesministerium fur Wirtschaft und Energie(BMWi)for funding number 16KN046744.
文摘The physical-mechanical,chemical,and durability characteristics of alkali-activated materials(AAMs)have been widely investigated.However,a critical gap in the literature is the lack of a comprehensive overview of recently published literature regarding the life cycle assessment(LCA)of these binders.This study aims to fill that gap by conducting a systematic literature review of globally published literature on the topic.This paper consolidates knowledge by searching different databases,focusing on LCA studies that used AAMs as pastes,mortars,concretes,bricks,and rammed earth/soil blocks.The selected articles were reviewed and categorized based on precursors,alkaline activators,functional units,system boundaries,life cycle inventory databases,allocation,impact methodologies,and software used.Additionally,this paper also critically analyzes the key challenges of LCA for AAMs.The major challenges were identified as selecting a functional unit,subjectivity in boundary systems,and data interpretation.This work concludes that AAMs show substantial advantages in global warming potential compared to ordinary Portland cement-based materials;however,the average of other categories such as marine ecotoxicity and ozone layer depletion has been reported to be higher than for the reference samples.
