Herein, a trimetallic Ni–Co–Zn perovskite fluoride (ABF3) (denoted as KNCZF) electrode material is explored for advanced aqueous supercabatteries (ASCBs), with KNCZF and activated carbon–FeBiCu@reduced graphene oxides (AC–FeBiCu@rGO) as cathode and anode, respectively, which outperform aqueous supercapacitors (ASCs) and batteries (ABs) with AC and FeBiCu@rGO anodes because of the synergistic effect of pseudocapacitive (KNCZF), capacitive (AC), and faradaic (FeBiCu@rGO) responses. One of the important findings is that the KNCZF shows a typical bulk phase conversion mechanism for charge storage in the alkaline media with the transition of ABF3 perovskite nanocrystals into amorphous metal oxides/(oxy)hydroxides nanosheets, showing the redox-active and redox-inert roles for the Ni/Co and Zn species, respectively, which can be deduced by various ex-situ techniques. Another interesting finding is that the redox-inert Zn species largely enhance the activity of Ni/Co redox-active species in the ABF3 materials, mainly owing to the promotion of surface electroactive sites, adsorption of OH?, and charge transfer of surface Ni/Co atoms by Zn-doping, which can be proved by ex-situ characterizations and theoretical calculations. Overall, this study reveals the structure–activity relationship and charge storage mechanisms of Zn-doping ABF3 materials for advanced ASCBs, showing a great impact on developing advanced electrochemical energy storage. 相似文献
The main task of local rough set model is to avoid the interference of complicated calculation and invalid information in the formation of approximation space. In this paper, we first present a local rough set model based on dominance relation to make the local rough set theory applicable to the ordered information system, then two kinds of local multigranulation rough set models in the ordered information system are constructed by extending the single granulation environment to a multigranulation case. Moreover, the updating processes of dynamic objects based on global (classical) and local multigranulation rough sets in the ordered information system are analyzed and compared carefully. It is addressed about how the rough approximation spaces of global multigranulation rough set and local multigranulation rough set change when the object set increase or decrease in an ordered information system. The relevant algorithms for updating approximations with dynamic objects on global and local multigranulation rough sets are provided in ordered information systems. To illustrate the superiority and the effectiveness of the proposed dynamic updating approaches in the ordered information system, experimental evaluation is performed using six datasets coming from the University of California-Irvine repository.
Neural Computing and Applications - Existing sequential recommendation methods focus on modeling the temporal relationships of users’ historical behaviors and excel in exploiting users’... 相似文献
This paper studied the structural design of a ceramic core and a blade, ceramic core localization, shell preparation, casting process, core leaching technology, and the heat treatment process of a single-crystal hollow turbine blade. The results show that the single-crystal structure solidification sequence of the blade platform is consistent with the cooling sequence and the pulling-out direction of the blade. The primary dendrites were obviously enlarged with the increase of the blade thickness owing to the change in the local cooling rate. Besides, the γ′ phase had a high uniform size distribution ranging from 0.40 to 0.60?µm after heat treatment, and the cubic degree was more homogeneous in comparison with the as-cast microstructure, which are favorable for the superalloy structure. Moreover, γ′ phase size gradually increased and its quantity gradually reduced owing to the increase of the wall thickness in the growth direction. 相似文献