Nickel-iron layered double hydroxides(NiFe LDHs) have been identified as one of the best promising electrocatalysts-candidates for oxygen evolution reaction(OER). However, the catalytic activity effected by interlayer...Nickel-iron layered double hydroxides(NiFe LDHs) have been identified as one of the best promising electrocatalysts-candidates for oxygen evolution reaction(OER). However, the catalytic activity effected by interlayer water molecules is ignored and rarely reported. Herein, Ni(OH)_2, NiFe LDHs vertically aligned Ni foam are designed for OER. As a contrast, the corresponding electrocatalysts with the removal of the interlayer water molecules(Ni(OH)_2-AT, NiFe LDHs-AT) are developed to probe into the influence of the interlayer water molecules towards OER. As expected, NiFe LDH nanoplates exhibit excellent catalytic performance and durability for water electrolysis in alkaline conditions with lower overpotential and smaller Tafel slope compared to those of NiFe LDHs-AT, which are influenced mainly by stability of crystal structure due to the existence of interlayer water molecules. The discovery opens up a similar pathway by controlling the amount of water molecules to boost catalytic performance for studying other electrocatalysts with heteroatom dopant.展开更多
This paper addresses multi-resource fair allocation: a fundamental research topic in cloud computing. To improve resource utilization under well-studied fairness constraints, we propose a new allocation mechanism call...This paper addresses multi-resource fair allocation: a fundamental research topic in cloud computing. To improve resource utilization under well-studied fairness constraints, we propose a new allocation mechanism called Dominant Resource with Bottlenecked Fairness(DRBF), which generalizes Bottleneck-aware Allocation(BAA) to the settings of Dominant Resource Fairness(DRF). We classify users into different queues by their dominant resources. The goals are to ensure that users in the same queue receive allocations in proportion to their fair shares while users in different queues receive allocations that maximize resource utilization subject to well-studied fairness properties such as those in DRF. Under DRBF, no user 1) is worse off sharing resources than dividing resources equally among all users; 2) prefers the allocation of another user; 3) can improve their own allocation without reducing other users' allocations; and(4) can benefit by misreporting their resource demands. Experiments demonstrate that the proposed allocation policy performs better in terms of high resource utilization than does DRF.展开更多
基金financially supported by the National Natural Science Foundation of China (51622102, 51571124, 21421001)MOST (2017YFA0206702)+3 种基金the 111 Project (B12015)the Natural Science Foundation of Tianjin (16PTSYJC00030)the Fundamental Research Funds for the Central Universitiesthe Tianjin Colle ge Students Innovation and Entrepreneurship Training Project (201814038024)。
文摘Nickel-iron layered double hydroxides(NiFe LDHs) have been identified as one of the best promising electrocatalysts-candidates for oxygen evolution reaction(OER). However, the catalytic activity effected by interlayer water molecules is ignored and rarely reported. Herein, Ni(OH)_2, NiFe LDHs vertically aligned Ni foam are designed for OER. As a contrast, the corresponding electrocatalysts with the removal of the interlayer water molecules(Ni(OH)_2-AT, NiFe LDHs-AT) are developed to probe into the influence of the interlayer water molecules towards OER. As expected, NiFe LDH nanoplates exhibit excellent catalytic performance and durability for water electrolysis in alkaline conditions with lower overpotential and smaller Tafel slope compared to those of NiFe LDHs-AT, which are influenced mainly by stability of crystal structure due to the existence of interlayer water molecules. The discovery opens up a similar pathway by controlling the amount of water molecules to boost catalytic performance for studying other electrocatalysts with heteroatom dopant.
基金financial support of the Oversea Study Program of the Guangzhou Elite Project(GEP)supported by the National Natural Science Foundation of China under Grant 61471173Guangdong Science Technology Project(no:2017A010101027)
文摘This paper addresses multi-resource fair allocation: a fundamental research topic in cloud computing. To improve resource utilization under well-studied fairness constraints, we propose a new allocation mechanism called Dominant Resource with Bottlenecked Fairness(DRBF), which generalizes Bottleneck-aware Allocation(BAA) to the settings of Dominant Resource Fairness(DRF). We classify users into different queues by their dominant resources. The goals are to ensure that users in the same queue receive allocations in proportion to their fair shares while users in different queues receive allocations that maximize resource utilization subject to well-studied fairness properties such as those in DRF. Under DRBF, no user 1) is worse off sharing resources than dividing resources equally among all users; 2) prefers the allocation of another user; 3) can improve their own allocation without reducing other users' allocations; and(4) can benefit by misreporting their resource demands. Experiments demonstrate that the proposed allocation policy performs better in terms of high resource utilization than does DRF.
