Large scale synthesis of high-efficiency bifunctional electrocatalyst based on cost-effective and earth-abundant transition metal for overall water splitting in the alkaline environment is indispensable for renewable ...Large scale synthesis of high-efficiency bifunctional electrocatalyst based on cost-effective and earth-abundant transition metal for overall water splitting in the alkaline environment is indispensable for renewable energy conversion.In this regard,meticulous design of active sites and probing their catalytic mechanism on both cathode and anode with different reaction environment at molecular-scale are vitally necessary.Herein,a coordination environment inheriting strategy is presented for designing low-coordination Ni^(2+)octahedra(L-Ni-8)atomic interface at a high concentration(4.6 at.%).Advanced spectroscopic techniques and theoretical calculations reveal that the self-matching electron delocalization and localization state at L-Ni-8 atomic interface enable an ideal reaction environment at both cathode and anode.To improve the efficiency of using the self-modification reaction environment at L-Ni-8,all of the structural features,including high atom economy,mass transfer,and electron transfer,are integrated together from atomic-scale to macro-scale.At high current density of 500 mA/cm2,the samples synthesized at gram-scale can deliver low hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)overpotentials of 262 and 348 mV,respectively.展开更多
Cloud computing and edge computing brought more software,which also brought a new danger of malicious software attacks.Data synchronization mechanisms of software can further help reverse data modifications.Based on t...Cloud computing and edge computing brought more software,which also brought a new danger of malicious software attacks.Data synchronization mechanisms of software can further help reverse data modifications.Based on the mechanisms,attackers can cover themselves behind the network and modify data undetected.Related knowledge of software reverse engineering can be organized as rules to accelerate the attacks,when attackers intrude cloud server to access the source or binary codes.Therefore,we proposed a novel method to resist this kind of reverse engineering by breaking these rules.Our method is based on software obfuscations and encryptions to enhance the security of distributed software and cloud services in the 5G era.Our method is capable of(1)replacing theoriginal assembly codes of theprotectedprogramwithequivalent assembly instructions inan iteration way,(2)obfuscating the control flow of the protected program to confuse attackers meanwhile keeps the program producing the same outputs,(3)encrypting data to confuse attackers.In addition,the approach can periodically and automatically modify the protected software binary codes,and the binary codes of the protected software are encrypted to resist static analysis and dynamic analysis.Furthermore,a simplified virtual machine is implemented to make the protected codes unreadable to attackers.Cloud game is one of the specific scenarios which needs low latency and strong data consistency.Cheat engine,Ollydbg,and Interactive Disassembler Professional(IDA)are used prevalently for games.Our improved methods can protect the software from the most vulnerable aspects.The improved dynamic code swapping and the simplified virtual machine technologies for cloud games are the main innovations.We inductively learned that our methods have been working well according to the security mechanisms and time complexity analysis.Experiments show that hidden dangers can be eliminated with efficient methods:Execution time and file sizes of the target codes can be multiple times than that of the original program codes which depend on specific program functions.展开更多
基金supported by the National Natural Science Foundation of China(No.21676300)the Shandong Provincial Natural Science Foundation(No.ZR2018MB035)+3 种基金the Fundamental Research Funds for the Central Universities(Nos.19CX02008A and 16CX06007A)PetroChina Innovation Foundation(No.2019D-5007-0401)Taishan Scholars Program of Shandong Province(No.tsqn201909065)Tsinghua University Initiative Scientific Research Program.
文摘Large scale synthesis of high-efficiency bifunctional electrocatalyst based on cost-effective and earth-abundant transition metal for overall water splitting in the alkaline environment is indispensable for renewable energy conversion.In this regard,meticulous design of active sites and probing their catalytic mechanism on both cathode and anode with different reaction environment at molecular-scale are vitally necessary.Herein,a coordination environment inheriting strategy is presented for designing low-coordination Ni^(2+)octahedra(L-Ni-8)atomic interface at a high concentration(4.6 at.%).Advanced spectroscopic techniques and theoretical calculations reveal that the self-matching electron delocalization and localization state at L-Ni-8 atomic interface enable an ideal reaction environment at both cathode and anode.To improve the efficiency of using the self-modification reaction environment at L-Ni-8,all of the structural features,including high atom economy,mass transfer,and electron transfer,are integrated together from atomic-scale to macro-scale.At high current density of 500 mA/cm2,the samples synthesized at gram-scale can deliver low hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)overpotentials of 262 and 348 mV,respectively.
基金supported by grants from Natural Science Foundation of Inner Mongolia Autonomous Region(No.2022MS06024)NSFC(No.61962040)+3 种基金Hainan Province Key R&D Program(ZDYF2022GXJS007,ZDYF2022GXJS010)Hainan Natural Science Foundation(620RC561)Hainan Province Higher Education and Teaching Reform Research Project(Hnjg2021ZD-3)Hainan Province Key Laboratory of Meteorological Disaster Prevention and Mitigation in the South China Sea,Open Fund Project(SCSF202210).
文摘Cloud computing and edge computing brought more software,which also brought a new danger of malicious software attacks.Data synchronization mechanisms of software can further help reverse data modifications.Based on the mechanisms,attackers can cover themselves behind the network and modify data undetected.Related knowledge of software reverse engineering can be organized as rules to accelerate the attacks,when attackers intrude cloud server to access the source or binary codes.Therefore,we proposed a novel method to resist this kind of reverse engineering by breaking these rules.Our method is based on software obfuscations and encryptions to enhance the security of distributed software and cloud services in the 5G era.Our method is capable of(1)replacing theoriginal assembly codes of theprotectedprogramwithequivalent assembly instructions inan iteration way,(2)obfuscating the control flow of the protected program to confuse attackers meanwhile keeps the program producing the same outputs,(3)encrypting data to confuse attackers.In addition,the approach can periodically and automatically modify the protected software binary codes,and the binary codes of the protected software are encrypted to resist static analysis and dynamic analysis.Furthermore,a simplified virtual machine is implemented to make the protected codes unreadable to attackers.Cloud game is one of the specific scenarios which needs low latency and strong data consistency.Cheat engine,Ollydbg,and Interactive Disassembler Professional(IDA)are used prevalently for games.Our improved methods can protect the software from the most vulnerable aspects.The improved dynamic code swapping and the simplified virtual machine technologies for cloud games are the main innovations.We inductively learned that our methods have been working well according to the security mechanisms and time complexity analysis.Experiments show that hidden dangers can be eliminated with efficient methods:Execution time and file sizes of the target codes can be multiple times than that of the original program codes which depend on specific program functions.
