Ga-doped Li_(7)La_(3)Zr_(2)O_(12)(Ga-LLZO)has long been considered as a promising garnet-type electrolyte candidate for all-solid-state lithium metal batteries(ASSLBs)due to its high room temperature ionic conductivit...Ga-doped Li_(7)La_(3)Zr_(2)O_(12)(Ga-LLZO)has long been considered as a promising garnet-type electrolyte candidate for all-solid-state lithium metal batteries(ASSLBs)due to its high room temperature ionic conductivity.However,the typical synthesis of Ga-LLZO is usually accompanied by the formation of undesired LiGaO_(2) impurity phase that causes severe instability of the electrolyte in contact with molten Li metal during half/full cell assembly.In this study,we show that by simply engineering the defect chemistry of Ga-LLZO,namely,the lithium deficiency level,LiGaO_(2) impurity phase is effectively inhibited in the final synthetic product.Consequently,defect chemistry engineered Ga-LLZO exhibits excellent electrochemical stability against lithium metal,while its high room temperature ionic conductivity(~1.9×10^(-3)S·cm^(-1))is well reserved.The assembled Li/Ga-LLZO/Li symmetric cell has a superior critical current density of 0.9 mA·cm^(-2),and cycles stably for 500 hours at a current density of 0.3 mA·cm^(-2).This research facilitates the potential commercial applications of high performance Ga-LLZO solid electrolytes in ASSLBs.展开更多
In recent years, China's increased interest in environmental protection has led to a promotion of energy-efficient dual fuel(diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose ...In recent years, China's increased interest in environmental protection has led to a promotion of energy-efficient dual fuel(diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose dangers of fire and explosion if a gas leak occurs. If explosions or fires occur in the engine rooms of a ship, heavy damage and losses will be incurred. In this paper, a fault tree model is presented that considers both fires and explosions in a dual fuel ship; in this model, dual fuel engine rooms are the top events. All the basic events along with the minimum cut sets are obtained through the analysis.The primary factors that affect accidents involving fires and explosions are determined by calculating the degree of structure importance of the basic events.According to these results, corresponding measures are proposed to ensure and improve the safety and reliability of Chinese inland dual fuel ships.展开更多
多色有机室温磷光(Room Temperature Phosphorescent,RTP)材料因其发射寿命长、颜色可调、生物相容性好以及激发态性质可调控等独特的性质,在显示技术、防伪、数据加密以及传感等领域展现出巨大的应用潜力,近年来受到了研究者的广泛关...多色有机室温磷光(Room Temperature Phosphorescent,RTP)材料因其发射寿命长、颜色可调、生物相容性好以及激发态性质可调控等独特的性质,在显示技术、防伪、数据加密以及传感等领域展现出巨大的应用潜力,近年来受到了研究者的广泛关注。然而,受限于有机材料的三重态激子固有的敏感性,其三重态发光性质的调控成为了一个重大挑战。因此,在有机体系中实现多色且稳定的RTP发射仍然是一项亟待解决的问题。本文旨在综述近年来在多色有机RTP材料设计方面所取得的进展,重点介绍了卤素效应、晶体工程、聚集体效应以及主客体掺杂策略。通过精心选择和设计磷光分子,结合分子内/分子间相互作用和聚集态调控,成功实现了多种颜色的RTP发射。希望本文能为多色RTP材料的合理设计提供一定的思路,并为多色RTP材料的各种前沿应用提供一定的指导。展开更多
为满足船东对MAN低速主机配置、机舱布置和船舶经济性的要求,分别对基于选择催化还原(Selective Catalytic Reduction,SCR)技术和废气再循环(Exhaust Gas Recirculation,EGR)技术的2种MAN低速主机配置方案的设计原理及辅助系统设计进行...为满足船东对MAN低速主机配置、机舱布置和船舶经济性的要求,分别对基于选择催化还原(Selective Catalytic Reduction,SCR)技术和废气再循环(Exhaust Gas Recirculation,EGR)技术的2种MAN低速主机配置方案的设计原理及辅助系统设计进行分析。从燃油、化学品消耗和机舱布置方面进行研究,为船东基于安装和运行成本考虑选择合适的减排技术方案提供参考。实例对比分析结果表明,虽然SCR配置方案的机舱布置相对困难,但目前其设备和燃油成本低于EGR配置方案,具有更好的经济性。随着燃油和设备价格的不断调整,可综合对比2种配置方案的经济性之后选择更优的方案。展开更多
基金financially supported by the National Natural Science Foundation of China (Grant No.52171221)the National Key Research and Development Program of China (Grant No.2019YFA0704900)。
文摘Ga-doped Li_(7)La_(3)Zr_(2)O_(12)(Ga-LLZO)has long been considered as a promising garnet-type electrolyte candidate for all-solid-state lithium metal batteries(ASSLBs)due to its high room temperature ionic conductivity.However,the typical synthesis of Ga-LLZO is usually accompanied by the formation of undesired LiGaO_(2) impurity phase that causes severe instability of the electrolyte in contact with molten Li metal during half/full cell assembly.In this study,we show that by simply engineering the defect chemistry of Ga-LLZO,namely,the lithium deficiency level,LiGaO_(2) impurity phase is effectively inhibited in the final synthetic product.Consequently,defect chemistry engineered Ga-LLZO exhibits excellent electrochemical stability against lithium metal,while its high room temperature ionic conductivity(~1.9×10^(-3)S·cm^(-1))is well reserved.The assembled Li/Ga-LLZO/Li symmetric cell has a superior critical current density of 0.9 mA·cm^(-2),and cycles stably for 500 hours at a current density of 0.3 mA·cm^(-2).This research facilitates the potential commercial applications of high performance Ga-LLZO solid electrolytes in ASSLBs.
基金Supported by Transformation of Scientific and Technological Achievements Special Fund(No.SBA2015020077)
文摘In recent years, China's increased interest in environmental protection has led to a promotion of energy-efficient dual fuel(diesel/natural gas) ships in Chinese inland rivers. A natural gas as ship fuel may pose dangers of fire and explosion if a gas leak occurs. If explosions or fires occur in the engine rooms of a ship, heavy damage and losses will be incurred. In this paper, a fault tree model is presented that considers both fires and explosions in a dual fuel ship; in this model, dual fuel engine rooms are the top events. All the basic events along with the minimum cut sets are obtained through the analysis.The primary factors that affect accidents involving fires and explosions are determined by calculating the degree of structure importance of the basic events.According to these results, corresponding measures are proposed to ensure and improve the safety and reliability of Chinese inland dual fuel ships.
文摘多色有机室温磷光(Room Temperature Phosphorescent,RTP)材料因其发射寿命长、颜色可调、生物相容性好以及激发态性质可调控等独特的性质,在显示技术、防伪、数据加密以及传感等领域展现出巨大的应用潜力,近年来受到了研究者的广泛关注。然而,受限于有机材料的三重态激子固有的敏感性,其三重态发光性质的调控成为了一个重大挑战。因此,在有机体系中实现多色且稳定的RTP发射仍然是一项亟待解决的问题。本文旨在综述近年来在多色有机RTP材料设计方面所取得的进展,重点介绍了卤素效应、晶体工程、聚集体效应以及主客体掺杂策略。通过精心选择和设计磷光分子,结合分子内/分子间相互作用和聚集态调控,成功实现了多种颜色的RTP发射。希望本文能为多色RTP材料的合理设计提供一定的思路,并为多色RTP材料的各种前沿应用提供一定的指导。
文摘为满足船东对MAN低速主机配置、机舱布置和船舶经济性的要求,分别对基于选择催化还原(Selective Catalytic Reduction,SCR)技术和废气再循环(Exhaust Gas Recirculation,EGR)技术的2种MAN低速主机配置方案的设计原理及辅助系统设计进行分析。从燃油、化学品消耗和机舱布置方面进行研究,为船东基于安装和运行成本考虑选择合适的减排技术方案提供参考。实例对比分析结果表明,虽然SCR配置方案的机舱布置相对困难,但目前其设备和燃油成本低于EGR配置方案,具有更好的经济性。随着燃油和设备价格的不断调整,可综合对比2种配置方案的经济性之后选择更优的方案。
