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Microstructure and thermoelectric properties of Bi_(0.5)Na_(0.02)Sb_(1.48-x)In_xTe_3 alloys fabricated by vacuum melting and hot pressing

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Rare Metals 2015年第11期34卷 770-775页

作者： Xing-Kai Duan Kong-Gang Hu Da-Hu Ma Wang-Nian Zhang yue-zhen jiang Shu-Chao Guo Center for New Energy Materials Research School of Mechanical and Materials Engineering Jiujiang University

The Bi0.5Na0.02Sb1.48-xInxTe3alloys（x =0.02-0.20） were synthesized by vacuum melting and hot pressing methods at 753 K,60 MPa for 30 *** of Na and In dual partial substitutions for Sb on the thermoelectric properties were investigated from 300 to 500 *** Sb with Na and In can enhance the Seebeck coefficient effectively near room *** electrical resistivity of the Na and In dual-doping samples is higher within the whole test temperature *** Bi0.5Na0.02Sb1.48-xInxTe3samples（x = 0.02,0.06） play a great role in optimizing the thermal *** for the Bi0.5Na0.02Sb1.46In0.02Te3alloy,the minimum value of thermal conductivity reaches 0.53 W·m-1·K-1at 320 *** thermoelectric performance of the Na and In dualdoped samples is greatly improved,and a figure of merit ZT of 1.26 is achieved at 300 K for the Bi0.5Na0.02Sb1.42In0.06Te3,representing 26%enhancement with respect to ZT = 1.0 of the undoped sample.

关键词： Microstructure Dual doping Hot pressing Thermal co

Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China

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Chinese Geographical Science 2024年第1期34卷 168-180页

作者： WANG yue jiang Yuting ZHU Guoxu School of Management Shenyang Normal UniversityShenyang110034China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130012China

It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food *** CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food *** is urgent to evaluate the CLSR at multiple spatio-temporal *** study took Liaoning Province in the black soil region of Northeast China as an *** on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to *** results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,*** addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the *** feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the *** results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment.

关键词： cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province,China

Numerical investigation of transient gas–solid heat transfer in a packed bed:Impact of intra-particle thermal diffusion

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Particuology 2024年第7期90卷 404-411页

作者： Hanqiao Che Yuanhe yue Zhaohua jiang Duan Li School of Mechanical Engineering Guangxi UniversityNanningGuangxi530004China School of Chemical Engineering University of BirminghamBirminghamB152TTUK Hebei Engineering Research Center of Advanced Energy Storage Technology and Equipment School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China Hebei Key Laboratory of Thermal Science and Energy Clean Utilization School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China School of Mechatronics and Vehicle Engineering Chongqing Jiaotong UniversityChongqing400074China School of Instrumentation and Opto-Electronic Engineering Beihang UniversityBeijing 100191China

The transient heat transfer behaviours in a packed bed have been studied using coupled computational fluid dynamics(CFD)and discrete element method(DEM).Intra-particle thermal diffusion,which is a crucial but rarely explored issue,is considered by introducing a one-dimensional diffusion equation in the DEM *** achieve a sufficiently long physical time of simulations,we further reduce the computational cost by applying periodic boundary condition to a small segment of the packed *** study demonstrates a shifting peak heat flow rate from the bottom to the top of the packed bed during the initial warming *** affirm that the influence of thermal diffusion within a particle is noteworthy only for particles exhibiting a high Biot number(e.g.,Bi=1.2).This insight enriches our understanding of heat transfer mechanisms in packed beds and their practical engineering applications.

关键词： Packed bed Intra-particle heat transfer CFD–DEM

考虑结构参数不确定性的月球探测器结构优化设计

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宇航学报 2021年第12期42卷 1502-1514页

作者：陈昭岳刘莉岳振江北京理工大学宇航学院飞行器动力学与控制教育部重点实验室北京100081

针对月球探测器结构优化过程中存在的分析耗时和结构参数不确定性影响问题,提出了考虑结构参数不确定性的月球探测器结构快速优化框架。优化框架基于多域子结构运动综合方法,建立了月球探测器结构多域子结构模型,实现了模型规模的降低,... 详细信息

针对月球探测器结构优化过程中存在的分析耗时和结构参数不确定性影响问题,提出了考虑结构参数不确定性的月球探测器结构快速优化框架。优化框架基于多域子结构运动综合方法,建立了月球探测器结构多域子结构模型,实现了模型规模的降低,提高了模型分析效率;基于区间场不确定性分析方法,建立了结构参数不确定性模型,并开展了探测器结构参数区间灵敏度分析;基于区间可能度理论实现了不确定性优化问题的转换。通过两个优化算例进行方法验证,优化分析结果表明,基于本文的结构优化框架,可以明显提高结构优化效率;通过与确定性优化结果对比,验证了考虑结构不确定性的结构优化可以提高分析结果的可靠性。

关键词：月球探测器力学环境动力学优化设计多域子结构方法区间不确定性

Hydrometallurgical recovery of lithium carbonate and iron phosphate from blended cathode materials of spent lithium-ion battery

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Rare Metals 2024年第3期43卷 1275-1287页

作者： Shao-Le Song Run-Qing Liu Miao-Miao Sun Ai-Gang zhen Fan-zhen Kong yue Yang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083China Zhejiang Tianneng New Materials Co. Ltd.Huzhou313103China

The recycling of cathode materials from spent lithium-ion battery has attracted extensive attention,but few research have focused on spent blended cathode *** reality,the blended materials of lithium iron phosphate and ternary are widely used in electric vehicles,so it is critical to design an effective recycling *** this study,an efficient method for recovering Li and Fe from the blended cathode materials of spent LiFePO_(4)and LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)batteries is ***,87%A1 was removed by alkali ***,91.65%Li,72.08%Ni,64.6%Co and 71.66%Mn were further separated by selective leaching with H_(2)SO_(4)and H_(2)O_(2).Li,Ni,Co and Mn in solution were recovered in the form of Li_(2)CO_(3)and hydroxide ***,98.38%Fe was leached from the residue by two stage process,and it is recovered as FePO_(4)·2H_(2)O with a purity of 99.5%by *** and P were present in FePO_(4)·2H_(2)O in amounts of 28.34%and 15.98%,***,the drift and control of various components were discussed,and cost-benefit analysis was used to assess the feasibility of potential application.

关键词： Spent lithium-ion battery Blended cathode materials Recovery Lithium carbonate Iron phosphate

Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN

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China Communications 2024年第6期21卷 23-39页

作者： jiang Jie Lyu Bin Chen Pengcheng Yang zhen School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology Nanjing UniversityNanjing 210003China

In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the *** formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource *** solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation ***,the tightness of applying the SDR is *** results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively.

关键词： active reconfigurable intelligent surface beamforming sum-rate maximization wireless powered communication network

A scalable one-pot strategy for the development of polymer electrolytes adaptable to room-temperature high-voltage lithium batteries

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Chinese Chemical Letters 2024年第3期35卷 461-467页

作者： yue Guo Xinxin Qu zhen Li Ruiyuan Tian Xiaokong Liu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Key Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education) College of PhysicsJilin UniversityChangchun 130012China

Poly(ethylene oxide)(PEO)polymer electrolytes(PEs)have been commercially applied in LiFePO_(4)||Li solid-state lithium batteries(SSLBs).However,it remains challenging to develop PEO-based PEs applicable to the high-voltage SSLBs with higher energy density,owing to the poor electrochemical stability of ***,we report a scalable strategy for fabricating PEO-based PEs with high-voltage compatibility,by exploiting a new mechanism to stabilize the cathode-electrolyte interface in the highvoltage *** protocol only involves a one-pot synthesis procedure to covalently crosslink the PEO chains,in the presence of high-content lithium bis(trifluoromethylsulphonyl)imide(LiTFSI)salts and N,N-dimethylformamide(DMF).LiTFSI-DMF supramolecular aggregates are formed and firmly embedded in the polymer network,endowing the PE with high room-temperature ionic *** dissociated and highly concentrated TFSI^-anions can enter the Helmholtz layer close to the high-voltage cathode,leading to the formation of a thin and homogeneous cathode electrolyte interface(CEI),mainly composed of LiF,on the *** CEI with high electrochemical stability can effectively stabilize the cathode-electrolyte interface,enabling long-term stable cycling of the high-voltage LiCoO_(2)||Li and nickelrich NCM_(622)||Li batteries at room *** simplicity and scalability of the strategy makes the reported PEO-based PE potentially applicable in high-voltage SSLBs in practice.

关键词： Lithium batteries Polymer electrolytes Poly(ethylene oxide) Energy density High-voltage cathodes

Ca_(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemical-looping oxidative dehydrogenation of ethane to ethylene

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Chinese Journal of Chemical Engineering 2024年第4期68卷 53-64页

作者： Weixiao Ding Kun Zhao Shican jiang zhen Huang Fang He College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541006China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of Ca_(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox catalysts(also known as oxygen carriers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significantly-nhanced the selectivity for-thylene generation from Ca_(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto Ca_(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox ***,formation of NaNO_(3) shell on the surface of Ca_(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise *** modulation contributed significantly to the enhanced selectivity for ethylene of the NaNO_(3)-doped Ca_(2)MnO_(4) *** findings provide compelling evidence for the potential of Ca_(2)MnO_(4)-layered perovskites as promising redox catalysts in the context of CL-ODH reactions.

关键词： Chemical-looping oxidative dehydrogenation Ethane Ethylene NaNO_(3)-doped Ca_(2)MnO_(4)redox catalyst Layered perovskites

Dynamic Hypergraph Modeling and Robustness Analysis for SIoT

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 3017-3034页

作者： yue Wan Nan jiang Ziyu Liu School of Information Engineering East China Jiaotong UniversityNanchang330013China

The Social Internet of Things(SIoT)integrates the Internet of Things(IoT)and social networks,taking into account the social attributes of objects and diversifying the relationship between humans and objects,which overcomes the limitations of the IoT’s focus on associations between *** Intelligence(AI)technology is rapidly *** is critical to build trustworthy and transparent systems,especially with system security issues coming to the *** paper emphasizes the social attributes of objects and uses hypergraphs to model the diverse entities and relationships in SIoT,aiming to build an SIoT hypergraph generation model to explore the complex interactions between entities in the context of intelligent *** hypergraph generation models impose too many constraints and fail to capture more details of real *** contrast,this paper proposes a hypergraph generation model that evolves dynamically over time,where only the number of nodes is *** combines node wandering with a forest fire model and uses two different methods to control the size of the *** new nodes are added,the model can promptly reflect changes in entities and relationships within *** results exhibit that our model can effectively replicate the topological structure of real-world *** also evaluate the vulnerability of the hypergraph under different attack strategies,which provides theoretical support for building a more robust intelligent SIoT hypergraph model and lays the foundation for building safer and more reliable systems in the future.

关键词： Large-scale artificial intelligence Social Internet of Things hypernetwork robustness analysis