Owing to its favorable thermodynamics and high density,NaAlH_(4) has been widely regarded as a potential hydrogen storage material,but its practical application is hindered by the sluggish kinetics,high operating temp...Owing to its favorable thermodynamics and high density,NaAlH_(4) has been widely regarded as a potential hydrogen storage material,but its practical application is hindered by the sluggish kinetics,high operating temperature and poor cycling stability.Here,taking advantage of Co-doped nanoporous carbon scaffolds as structural host,we develop a new strategy to balance the synergistic effect between the catalytic role of Co nanoparticles and the nanoconfinement role of porous carbon scaffolds via the controllable etching of Co nanoparticles towards enhanced hydrogen storage performance of NaAlH_(4).The etching of Co nanoparticles creates extra void spaces nearby catalytically active Co nanoparticles,which not only exerts the catalytic effect of Co nanoparticles,but also improves the nanoconfinement role in maintaining the cycling stability towards increased loading ratio and hence high systematic capacity.Induced by this balanced synergistic effect,the peak temperature for the dehydrogenation of NaAlH_(4) could be reduced to 164°C,97°C lower than the bulk counterpart,even under an ultrahigh loading ratio of 67%,and more importantly,the reversible systematic hydrogen storage capacity could still reach 3.3 wt.%after 5 cycles.This work opens up a new avenue to improve the hydrogen storage performance of various complex hydrides.展开更多
LiAIH4 doped with Ni and Ce（SO4）2 additives and the effect of doping on temperature and hydrogen release were studied by pressure-content-temperature （PCT） experiment and X-ray diffraction （XRD） analysis. It is ...LiAIH4 doped with Ni and Ce（SO4）2 additives and the effect of doping on temperature and hydrogen release were studied by pressure-content-temperature （PCT） experiment and X-ray diffraction （XRD） analysis. It is indicated that doping with Ni induces a significant decrease in temperature in the first step and LiA1H4 doped with 1mol% Ni presents the most absorption of hydrogen. Doping with Ce（S04）2 also causes a marked decrease, while the amount of hydrogen release changes only slightly. The results from X-ray diffraction analysis show that doping does not cause any structural change; Ni and Ce-containing phases are not observed at room temoerature or even at 250℃.展开更多
深圳外科论坛于10月19日在香港大学深圳医院召开。强大的讲者阵容是会议一大亮点,讲者级别堪比欧洲胸外科医师学会(European Society of Thoracic Surgeons,ESTS)会议,包括中国胸外科的"大佬",如何建行、刘伦旭、方文涛等几...深圳外科论坛于10月19日在香港大学深圳医院召开。强大的讲者阵容是会议一大亮点,讲者级别堪比欧洲胸外科医师学会(European Society of Thoracic Surgeons,ESTS)会议,包括中国胸外科的"大佬",如何建行、刘伦旭、方文涛等几位教授,国外胸外科泰斗则包括有单孔手术的鼻祖Gaetano Rocco教授,堪称印度机器人手术之王的Ali Zamir Khan教授,以及来自韩国、活跃于各大重要会议并正领导着微创胸腔镜手术培训项目的 Sanghoon Jheon教授,他以开展微创胸腔镜外科闻名于亚洲。在食管方面,台湾的Jang-Ming Lee教授和日本的Harushi Udagawa教授等皆是胸外科的佼佼者。为期一天的会议安排紧凑,具体分为胸外科技术新领域(Thoracic Surgery on the Horizon)、微创胸外科(Minimally Invasive Thoracic Surgery)、胸外科疾病治疗前瞻(Advances in Treatment of Thoracic Diseases)、手术演示(Sunday Afternoon at the Movies)四个版块,旨在让听众可以在一天之内听到不同的声音。会议结束之时,AME编辑有幸采访到会议主持兼讲者司徒达麟(Alan Sihoe)教授跟我们分享他这次会议的体会。。展开更多
This paper starts from the analysis of how Alan Turing proceeded to build the notion of computability in his famous 1936 text ＂On computable numbers, with an application to the Entscheidungsproblem＂. Looking in deta...This paper starts from the analysis of how Alan Turing proceeded to build the notion of computability in his famous 1936 text ＂On computable numbers, with an application to the Entscheidungsproblem＂. Looking in detail at his stepwise construction, which starts from the materialities to achieve a satisfactory level of abstraction, it is considered how his way of doing mathematics was one that constructs mathematical knowledge by evading a definite separation between matter and form; in this way, making the world and language come together. Following the same line of reasoning, it is argued in this paper that the abstract and the concrete, the deduction and the induction, the technical and the social as well as the objective and the subjective are unthinkable as pure entities. By considering the controversies and discussions from the mid-nineteenth century until now, it is shown that local （social） elements necessarily participate in what is usually considered ＂technical content＂ or ＂objectivity＂. While Alan Turing was a precursor of what today might be said to be an ＂anthropological approach to mathematical culture＂, unveiling and reviving approaches that enable the axis of authority for mathematics, logic and computing to be shifted, he also opened different paths for the construction of a variety of mathematical knowledge as well.展开更多
基金This work was partially supported by the National Key R&D Program of China(No.2018YFB1502101)National Science Fund for Distinguished Young Scholars(51625102)+3 种基金the National Natural Science Foundation of China(51971065,51901045)the Innovation Program of Shanghai Municipal Education Commission(2019-01-07-00-07-E00028)the Open Fund of the Guangdong Provincial Key Laboratory of Advanced Energy Storage Materialsthe Programs for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning。
文摘Owing to its favorable thermodynamics and high density,NaAlH_(4) has been widely regarded as a potential hydrogen storage material,but its practical application is hindered by the sluggish kinetics,high operating temperature and poor cycling stability.Here,taking advantage of Co-doped nanoporous carbon scaffolds as structural host,we develop a new strategy to balance the synergistic effect between the catalytic role of Co nanoparticles and the nanoconfinement role of porous carbon scaffolds via the controllable etching of Co nanoparticles towards enhanced hydrogen storage performance of NaAlH_(4).The etching of Co nanoparticles creates extra void spaces nearby catalytically active Co nanoparticles,which not only exerts the catalytic effect of Co nanoparticles,but also improves the nanoconfinement role in maintaining the cycling stability towards increased loading ratio and hence high systematic capacity.Induced by this balanced synergistic effect,the peak temperature for the dehydrogenation of NaAlH_(4) could be reduced to 164°C,97°C lower than the bulk counterpart,even under an ultrahigh loading ratio of 67%,and more importantly,the reversible systematic hydrogen storage capacity could still reach 3.3 wt.%after 5 cycles.This work opens up a new avenue to improve the hydrogen storage performance of various complex hydrides.
基金supported by the National High-Tech Research and Development Program (No.2006AA05Z132)the Program of the Ministry of Education of China for Changjiang Scholars and Innovative Research Teams in Universities (No.I2P407)
文摘LiAIH4 doped with Ni and Ce（SO4）2 additives and the effect of doping on temperature and hydrogen release were studied by pressure-content-temperature （PCT） experiment and X-ray diffraction （XRD） analysis. It is indicated that doping with Ni induces a significant decrease in temperature in the first step and LiA1H4 doped with 1mol% Ni presents the most absorption of hydrogen. Doping with Ce（S04）2 also causes a marked decrease, while the amount of hydrogen release changes only slightly. The results from X-ray diffraction analysis show that doping does not cause any structural change; Ni and Ce-containing phases are not observed at room temoerature or even at 250℃.
文摘深圳外科论坛于10月19日在香港大学深圳医院召开。强大的讲者阵容是会议一大亮点,讲者级别堪比欧洲胸外科医师学会(European Society of Thoracic Surgeons,ESTS)会议,包括中国胸外科的"大佬",如何建行、刘伦旭、方文涛等几位教授,国外胸外科泰斗则包括有单孔手术的鼻祖Gaetano Rocco教授,堪称印度机器人手术之王的Ali Zamir Khan教授,以及来自韩国、活跃于各大重要会议并正领导着微创胸腔镜手术培训项目的 Sanghoon Jheon教授,他以开展微创胸腔镜外科闻名于亚洲。在食管方面,台湾的Jang-Ming Lee教授和日本的Harushi Udagawa教授等皆是胸外科的佼佼者。为期一天的会议安排紧凑,具体分为胸外科技术新领域(Thoracic Surgery on the Horizon)、微创胸外科(Minimally Invasive Thoracic Surgery)、胸外科疾病治疗前瞻(Advances in Treatment of Thoracic Diseases)、手术演示(Sunday Afternoon at the Movies)四个版块,旨在让听众可以在一天之内听到不同的声音。会议结束之时,AME编辑有幸采访到会议主持兼讲者司徒达麟(Alan Sihoe)教授跟我们分享他这次会议的体会。。
文摘This paper starts from the analysis of how Alan Turing proceeded to build the notion of computability in his famous 1936 text ＂On computable numbers, with an application to the Entscheidungsproblem＂. Looking in detail at his stepwise construction, which starts from the materialities to achieve a satisfactory level of abstraction, it is considered how his way of doing mathematics was one that constructs mathematical knowledge by evading a definite separation between matter and form; in this way, making the world and language come together. Following the same line of reasoning, it is argued in this paper that the abstract and the concrete, the deduction and the induction, the technical and the social as well as the objective and the subjective are unthinkable as pure entities. By considering the controversies and discussions from the mid-nineteenth century until now, it is shown that local （social） elements necessarily participate in what is usually considered ＂technical content＂ or ＂objectivity＂. While Alan Turing was a precursor of what today might be said to be an ＂anthropological approach to mathematical culture＂, unveiling and reviving approaches that enable the axis of authority for mathematics, logic and computing to be shifted, he also opened different paths for the construction of a variety of mathematical knowledge as well.
