Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc den...Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc dendrite growth and side reactions of the zinc anode decrease the sta-bility of Zn batteries.We report the synthesis of an air-oxid-ized carbon nanotube(O-CNT)film by chemical vapor de-position followed by heat treatment in air which is used as a protective layer on the Zn foil to suppress zinc dendrite growth.The increase in the hydrophilicity of the O-CNT film caused by air oxidation facilitates zinc deposition between the film and the anode instead of deposition on the film surface.The porous structure of the O-CNT film homogenizes the Zn^(2+)ion flux and the electric field on the surface of the Zn foil,leading to the uniform deposition of Zn.As a result,a O-CNT@Zn symmetric cell has a much better cycling stability with a life of more than 3000 h at 1 mA cm^(−2) with a capacity of 1 mAh cm^(−2),and values of more than 2000 h and 1 mAh cm^(−2) at 5 mA cm^(−2).In addition,a O-CNT@Zn||Mn^(2+)inserted hydrated vanadium pentoxide(MnVOH)full cell has a better rate per-formance than a Zn||MnVOH cell,achieving a high discharge capacity of 194 mAh g^(−1) at a high current density of 8 A g^(−1).In a long-term cycling test,the O-CNT@Zn||MnVOH full cell has a capacity retention of 58.8%after 2000 cycles at a current density of 5 A·g^(−1).展开更多
针对延迟容忍网络中存在的数据传输时延较高、摆渡节点间协作性不高,以及如何最优分配摆渡节点等问题,提出一种基于位置信息的摆渡节点延迟容忍网络路由算法(ferries routing mechanism based on location information for delay tolera...针对延迟容忍网络中存在的数据传输时延较高、摆渡节点间协作性不高,以及如何最优分配摆渡节点等问题,提出一种基于位置信息的摆渡节点延迟容忍网络路由算法(ferries routing mechanism based on location information for delay tolerant network,FRLI)。基于节点位置信息,定义基于位置信息的数据传输机制,通过划分摆渡节点隶属的区域,根据摆渡节点在网络中的初始分布状况,合理分配网络中摆渡节点分布,通过交换彼此区域内缓存的网络节点信息,获取有利于当前区域内数据传输的有效信息,提高区域内数据传输效率;基于节点区域信息,确认目的节点是否属于当前区域后,直接将数据投递至网关节点,渐次转发至目的节点所在区域,有效提高数据传输效率。仿真结果表明,与当前MURA算法、SIRA算法相比,该算法具有更低的数据传输时延与更高的传输效率。展开更多
基金supported by the National Natural Science Foundation of China(22179093 and21905202)。
文摘Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc dendrite growth and side reactions of the zinc anode decrease the sta-bility of Zn batteries.We report the synthesis of an air-oxid-ized carbon nanotube(O-CNT)film by chemical vapor de-position followed by heat treatment in air which is used as a protective layer on the Zn foil to suppress zinc dendrite growth.The increase in the hydrophilicity of the O-CNT film caused by air oxidation facilitates zinc deposition between the film and the anode instead of deposition on the film surface.The porous structure of the O-CNT film homogenizes the Zn^(2+)ion flux and the electric field on the surface of the Zn foil,leading to the uniform deposition of Zn.As a result,a O-CNT@Zn symmetric cell has a much better cycling stability with a life of more than 3000 h at 1 mA cm^(−2) with a capacity of 1 mAh cm^(−2),and values of more than 2000 h and 1 mAh cm^(−2) at 5 mA cm^(−2).In addition,a O-CNT@Zn||Mn^(2+)inserted hydrated vanadium pentoxide(MnVOH)full cell has a better rate per-formance than a Zn||MnVOH cell,achieving a high discharge capacity of 194 mAh g^(−1) at a high current density of 8 A g^(−1).In a long-term cycling test,the O-CNT@Zn||MnVOH full cell has a capacity retention of 58.8%after 2000 cycles at a current density of 5 A·g^(−1).
文摘针对延迟容忍网络中存在的数据传输时延较高、摆渡节点间协作性不高,以及如何最优分配摆渡节点等问题,提出一种基于位置信息的摆渡节点延迟容忍网络路由算法(ferries routing mechanism based on location information for delay tolerant network,FRLI)。基于节点位置信息,定义基于位置信息的数据传输机制,通过划分摆渡节点隶属的区域,根据摆渡节点在网络中的初始分布状况,合理分配网络中摆渡节点分布,通过交换彼此区域内缓存的网络节点信息,获取有利于当前区域内数据传输的有效信息,提高区域内数据传输效率;基于节点区域信息,确认目的节点是否属于当前区域后,直接将数据投递至网关节点,渐次转发至目的节点所在区域,有效提高数据传输效率。仿真结果表明,与当前MURA算法、SIRA算法相比,该算法具有更低的数据传输时延与更高的传输效率。