In the present work,Fe–Mn–Al–C powder mixtures were manufactured by elemental powders with different ball milling time,and the porous high-Mn and high-Al steel was fabricated by powder sintering.The results indicat...In the present work,Fe–Mn–Al–C powder mixtures were manufactured by elemental powders with different ball milling time,and the porous high-Mn and high-Al steel was fabricated by powder sintering.The results indicated that the powder size significantly decreased,and the morphology of the Fe powder tended to be increasingly flat as the milling time increased.However,the prolonged milling duration had limited impact on the phase transition of the powder mixture.The main phases of all the samples sintered at 640℃ were α-Fe,α-Mn and Al,and a small amount of Fe2Al5 and Al8Mn5.When the sintering temperature increased to 1200℃,the phase composition was mainly comprised of γ-Fe and α-Fe.The weight loss fraction of the sintered sample decreased with milling time,i.e.,8.3wt% after 20 h milling compared to15.3wt% for 10 h.The Mn depletion region(MDR) for the 10,15,and 20 h milled samples was about 780,600,and 370 μm,respectively.The total porosity of samples sintered at 640℃ decreased from ~46.6vol% for the 10 h milled powder to ~44.2vol% for 20 h milled powder.After sintering at 1200℃,the total porosity of sintered samples prepared by 10 and 20 h milled powder was ~58.3vol% and ~51.3vol%,respectively.The compressive strength and ductility of the 1200℃ sintered porous steel increased as the milling time increased.展开更多
The issues of reducing CO_2 levels in the atmo-sphere, sustainably utilizing natural mineral resources,and dealing with indus trial waste offer challenging opportunities for sustainable development in energy and the e...The issues of reducing CO_2 levels in the atmo-sphere, sustainably utilizing natural mineral resources,and dealing with indus trial waste offer challenging opportunities for sustainable development in energy and the environment. The latest advances in CO_2 mineralization technology involving natural minerals and industrial waste are summarized in this paper, with great emphasis on the advancement of fundamental science, economic evaluation, and engineering applications. We discuss several lead-ing large-scale CO_2 mineralization methodologies from a techn ical and engineering-science perspective. For each technology option, we give an overview of the technical parameters, reaction pathway, reactivity, procedural scheme, and laboratorial and pilot devices. Furthermore, we present a discussion of each technology based on experimental results and the literature. Finally, current gaps in knowledge are identified in the conclusion, and an overview of the challenges and opportunities for future research in this field is provided.展开更多
Based on the recent development of renewable energy utilization technology,in addition to centralized photovol-taic power plants,distributed photovoltaic power generation systems represented by building-integrated pho...Based on the recent development of renewable energy utilization technology,in addition to centralized photovol-taic power plants,distributed photovoltaic power generation systems represented by building-integrated photo-voltaic systems are frequently employed for power supply.Therefore,in the architectural design,the double-glass photovoltaic module used in the integrated photovoltaic building system puts forward a higher load-bearing capa-city requirement and the corresponding simplified method of carrying capacity check.This article focuses on the simplified method of checking the bearing capacity of the four-sided simply supported double-glass photovoltaic module.First,the principle of equivalent stiffness is used to calculate the effective thickness.Then,the rationality of this approach is verified by comparing the bending states of sandwich panels under different shear moduli.The double-glass photovoltaic module is equivalent to a single-layer board,and its effectiveness is verified by compar-ing the impact test results of the double-glass photovoltaic module with the results of the single-layer board.But the comparison with the test results shows that,from the perspective of architectural design,the effective thick-ness results in this paper can ensure that the building structure has sufficient bearing capacity,but the four-side simply supported boundary theory cannot fully reflect the calculation of the bearing capacity of the four-side clamped double-glass photovoltaic module.展开更多
基金financially supported by the National Key R&D Program of China(No.2021YFB3802300)the National Natural Science Foundation of China(No.51804239)Guangdong Major Project of Basic and Applied Basic Research,China(No.2021B0301030001)。
文摘In the present work,Fe–Mn–Al–C powder mixtures were manufactured by elemental powders with different ball milling time,and the porous high-Mn and high-Al steel was fabricated by powder sintering.The results indicated that the powder size significantly decreased,and the morphology of the Fe powder tended to be increasingly flat as the milling time increased.However,the prolonged milling duration had limited impact on the phase transition of the powder mixture.The main phases of all the samples sintered at 640℃ were α-Fe,α-Mn and Al,and a small amount of Fe2Al5 and Al8Mn5.When the sintering temperature increased to 1200℃,the phase composition was mainly comprised of γ-Fe and α-Fe.The weight loss fraction of the sintered sample decreased with milling time,i.e.,8.3wt% after 20 h milling compared to15.3wt% for 10 h.The Mn depletion region(MDR) for the 10,15,and 20 h milled samples was about 780,600,and 370 μm,respectively.The total porosity of samples sintered at 640℃ decreased from ~46.6vol% for the 10 h milled powder to ~44.2vol% for 20 h milled powder.After sintering at 1200℃,the total porosity of sintered samples prepared by 10 and 20 h milled powder was ~58.3vol% and ~51.3vol%,respectively.The compressive strength and ductility of the 1200℃ sintered porous steel increased as the milling time increased.
基金finance support of the Ministry of Science and Technology (State Key Research Plan, 2013BAC12B00)the National Natural Science Foundation of China (21336004 and 51254002)
文摘The issues of reducing CO_2 levels in the atmo-sphere, sustainably utilizing natural mineral resources,and dealing with indus trial waste offer challenging opportunities for sustainable development in energy and the environment. The latest advances in CO_2 mineralization technology involving natural minerals and industrial waste are summarized in this paper, with great emphasis on the advancement of fundamental science, economic evaluation, and engineering applications. We discuss several lead-ing large-scale CO_2 mineralization methodologies from a techn ical and engineering-science perspective. For each technology option, we give an overview of the technical parameters, reaction pathway, reactivity, procedural scheme, and laboratorial and pilot devices. Furthermore, we present a discussion of each technology based on experimental results and the literature. Finally, current gaps in knowledge are identified in the conclusion, and an overview of the challenges and opportunities for future research in this field is provided.
基金This research was funded by the National Key Research and Development Program of China:Newton Fund-China-UK Research and Innovations Bridges(No.2016YFE0124500).
文摘Based on the recent development of renewable energy utilization technology,in addition to centralized photovol-taic power plants,distributed photovoltaic power generation systems represented by building-integrated photo-voltaic systems are frequently employed for power supply.Therefore,in the architectural design,the double-glass photovoltaic module used in the integrated photovoltaic building system puts forward a higher load-bearing capa-city requirement and the corresponding simplified method of carrying capacity check.This article focuses on the simplified method of checking the bearing capacity of the four-sided simply supported double-glass photovoltaic module.First,the principle of equivalent stiffness is used to calculate the effective thickness.Then,the rationality of this approach is verified by comparing the bending states of sandwich panels under different shear moduli.The double-glass photovoltaic module is equivalent to a single-layer board,and its effectiveness is verified by compar-ing the impact test results of the double-glass photovoltaic module with the results of the single-layer board.But the comparison with the test results shows that,from the perspective of architectural design,the effective thick-ness results in this paper can ensure that the building structure has sufficient bearing capacity,but the four-side simply supported boundary theory cannot fully reflect the calculation of the bearing capacity of the four-side clamped double-glass photovoltaic module.
