Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and ...Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and feeding behavior of the seahorse,Hippocampus erectus were studied.The growth parameters,pollutant bioaccumulation,enzymatic response,and feeding dynamics were extensively analyzed.Seahorses exposed to microplastics-borne B[a]P and heavy metals exhibited notable reductions in body length and weight,as well as in survival rates,indicating severe stress from these contaminants.The accumulation of pollutant particularly B[a]P in seahorse exceeded China’s national regulatory limit of 5μg/kg,and the B[a]P accumulation in seahorses was obviously aided by HDPE microplastics,posing a risk to marine organisms and human health via the food chain.The adaptive response of the seahorses was evident shown in the elevation of antioxidant enzyme activities,which is a biological mechanism to mitigate oxidative stress induced by the pollutants.However,this physiological adaptation comes at a cost,as evidenced by marked changes in the feeding behavior.Results show that the efficiency and frequency of feeding were greatly reduced,indicating a heavy impact on the ecological role and survival of this marine creature in polluted habitats.This research offers a crucial perspective on the compound threats of microplastics and associated pollutants in marine ecosystems.It highlights the urgent need develop comprehensive strategies to address these environmental issues.The findings are an important contribution to ecotoxicology,providing a deeper understanding of how microplastics act as vectors for other contaminants and their profound effects on marine life,especially species like seahorses.This study calls for action to strengthen environmental policies and practices aimed at mitigating the impact of marine pollution.展开更多
随着万物互联和5G时代的到来,移动用户需要处理的数据量与其处理数据能力不匹配。将大量任务卸载到有限的边缘服务器上执行势必会产生竞争,拍卖模型的引入可以解决用户之间对资源的竞争问题。目前大多基于拍卖的任务卸载工作忽略了任务...随着万物互联和5G时代的到来,移动用户需要处理的数据量与其处理数据能力不匹配。将大量任务卸载到有限的边缘服务器上执行势必会产生竞争,拍卖模型的引入可以解决用户之间对资源的竞争问题。目前大多基于拍卖的任务卸载工作忽略了任务的期限感知,普遍的任务卸载工作只单一考虑延迟敏感任务,并且未考虑到保证卸载过程的安全性。基于此,提出了一种基于拍卖的期限感知任务卸载(Auction Based Deadline-aware Task Offloading,ABDTO)策略,利用基于智能合约的拍卖机制实现期限感知任务(延迟敏感型任务和非延迟敏感型任务)到边缘服务器的最优分配,以总效用(即总利润)作为评价标准,实现移动用户和边缘服务器的共赢。利用启发式遗传算法进行仿真实验,相比TACD,UPPER和RND算法,ABDTO策略的整体效用更高,最后利用Remix和Ganache等建立以太坊私有区块链网络进行仿真,证明了所提策略的正确性和可行性。展开更多
TiNb_(2)O_(7) is an advanced anode material for high-energy density lithium-ion batteries(LIBs) due to its considerable specific capacity and satisfactory safety.However,its rate capability is limited by its poor ioni...TiNb_(2)O_(7) is an advanced anode material for high-energy density lithium-ion batteries(LIBs) due to its considerable specific capacity and satisfactory safety.However,its rate capability is limited by its poor ionic conductivity and electronic conductivity.To solve this problem,TiNb_(2)O_(7) with W^(6+) doping was synthesized by a convenient solid-state method.The doping of W^(6+) will lead to arranging cation mixing and charge compensation.The cation rearrangement creates a new Li-conductive environment for lithiation,resulting in a low-energy barrier and the fast Li^(+)storage/diffusion.The results show that the Li^(+)diffusion coefficient of W_(0.06)Ti_(0.91)Nb_(2)O_(7) is increased by 9.96 times greater than that of TiNb_(2)O_(7).Besides,as the calculation proves,due to the partial reduction of the Nb^(5+)and Ti^(4+) caused by charge compensation,W^(6+)doping results in low charge transfer resistance and excellent electronic conductivity.Moreover,W^(6+) doping accounts for a high pseudocapacitive contribution.At the scan rate of 1 mV·s^(-1),the pseudocapacitive contribution for TiNb_(2)O_(7) is 78%,while that for W_(0.06)Ti_(0.91)Nb_(2)O_(7) increases to 83%.The reversible specific capacity of W_(0.06)Ti_(0.91)Nb_(2)O_(7) after 600 cycles is maintained at 148.90mAh·g^(-1) with a loss of only 16.37% at 10.0C.Also,it delivers a commendable capacity of 161.99 mAh·g^(-1) at20.0C.Even at 30.0C,it still retains a satisfactory capacity of 147.22 mAh·g^(-1),much higher than TiNb_(2)O_(7)(97.49mAh·g^(-1)).Our present study provides ideas for the development of electrode materials for lithium-ion batteries.展开更多
基金Supported by the Marine Economic Development Project(No.GDNRC[2022]36)the National Key Research and Development Program of China(No.2018YFD0900206)the Tianjin Science and Technology Program Project(No.21YDTPJC00340)。
文摘Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and feeding behavior of the seahorse,Hippocampus erectus were studied.The growth parameters,pollutant bioaccumulation,enzymatic response,and feeding dynamics were extensively analyzed.Seahorses exposed to microplastics-borne B[a]P and heavy metals exhibited notable reductions in body length and weight,as well as in survival rates,indicating severe stress from these contaminants.The accumulation of pollutant particularly B[a]P in seahorse exceeded China’s national regulatory limit of 5μg/kg,and the B[a]P accumulation in seahorses was obviously aided by HDPE microplastics,posing a risk to marine organisms and human health via the food chain.The adaptive response of the seahorses was evident shown in the elevation of antioxidant enzyme activities,which is a biological mechanism to mitigate oxidative stress induced by the pollutants.However,this physiological adaptation comes at a cost,as evidenced by marked changes in the feeding behavior.Results show that the efficiency and frequency of feeding were greatly reduced,indicating a heavy impact on the ecological role and survival of this marine creature in polluted habitats.This research offers a crucial perspective on the compound threats of microplastics and associated pollutants in marine ecosystems.It highlights the urgent need develop comprehensive strategies to address these environmental issues.The findings are an important contribution to ecotoxicology,providing a deeper understanding of how microplastics act as vectors for other contaminants and their profound effects on marine life,especially species like seahorses.This study calls for action to strengthen environmental policies and practices aimed at mitigating the impact of marine pollution.
文摘随着万物互联和5G时代的到来,移动用户需要处理的数据量与其处理数据能力不匹配。将大量任务卸载到有限的边缘服务器上执行势必会产生竞争,拍卖模型的引入可以解决用户之间对资源的竞争问题。目前大多基于拍卖的任务卸载工作忽略了任务的期限感知,普遍的任务卸载工作只单一考虑延迟敏感任务,并且未考虑到保证卸载过程的安全性。基于此,提出了一种基于拍卖的期限感知任务卸载(Auction Based Deadline-aware Task Offloading,ABDTO)策略,利用基于智能合约的拍卖机制实现期限感知任务(延迟敏感型任务和非延迟敏感型任务)到边缘服务器的最优分配,以总效用(即总利润)作为评价标准,实现移动用户和边缘服务器的共赢。利用启发式遗传算法进行仿真实验,相比TACD,UPPER和RND算法,ABDTO策略的整体效用更高,最后利用Remix和Ganache等建立以太坊私有区块链网络进行仿真,证明了所提策略的正确性和可行性。
基金financially supported by the National Natural Science Foundation of China (Nos. 52274299, 52004103 and 51974137)the Postdoctoral Science Foundation of China (Nos. 2021M691321 and 2020M671361)the Postdoctoral Science Foundation of Jiangsu Province (No. 2020Z090)。
文摘TiNb_(2)O_(7) is an advanced anode material for high-energy density lithium-ion batteries(LIBs) due to its considerable specific capacity and satisfactory safety.However,its rate capability is limited by its poor ionic conductivity and electronic conductivity.To solve this problem,TiNb_(2)O_(7) with W^(6+) doping was synthesized by a convenient solid-state method.The doping of W^(6+) will lead to arranging cation mixing and charge compensation.The cation rearrangement creates a new Li-conductive environment for lithiation,resulting in a low-energy barrier and the fast Li^(+)storage/diffusion.The results show that the Li^(+)diffusion coefficient of W_(0.06)Ti_(0.91)Nb_(2)O_(7) is increased by 9.96 times greater than that of TiNb_(2)O_(7).Besides,as the calculation proves,due to the partial reduction of the Nb^(5+)and Ti^(4+) caused by charge compensation,W^(6+)doping results in low charge transfer resistance and excellent electronic conductivity.Moreover,W^(6+) doping accounts for a high pseudocapacitive contribution.At the scan rate of 1 mV·s^(-1),the pseudocapacitive contribution for TiNb_(2)O_(7) is 78%,while that for W_(0.06)Ti_(0.91)Nb_(2)O_(7) increases to 83%.The reversible specific capacity of W_(0.06)Ti_(0.91)Nb_(2)O_(7) after 600 cycles is maintained at 148.90mAh·g^(-1) with a loss of only 16.37% at 10.0C.Also,it delivers a commendable capacity of 161.99 mAh·g^(-1) at20.0C.Even at 30.0C,it still retains a satisfactory capacity of 147.22 mAh·g^(-1),much higher than TiNb_(2)O_(7)(97.49mAh·g^(-1)).Our present study provides ideas for the development of electrode materials for lithium-ion batteries.
