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Challenges and prospects for room temperature solid-state sodiumsulfur batteries

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Nano Research 2024年第3期17卷 1402-1426页

作者： Yashuang qiu Jing Xu Research Center of Grid Energy Storage and Battery Application School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China

Room temperature sodium-sulfur(Na-S)batteries,known for their high energy density and low cost,are one of the most promising next-generation energy storage ***,the polysulfide shuttling and uncontrollable Na dendrite growth as well as safety issues caused by the use of organic liquid electrolytes in Na-S cells,have severely hindered their ***-state electrolytes instead of liquid electrolytes are considered to be the most direct and effective solution to solve the above ***,its practical application is still greatly challenged due to the poor interfacial compatibility between the all-solid-state electrolytes and the anode/cathode,ionic conductivity,and the shuttle effect caused by the presence of liquid phase in the quasi-solid-state *** paper presents a comprehensive review of solid-state Na-S batteries from the perspective of regulating interfacial compatibility and improving ionic conductivity as well as suppressing polysulfide *** to different components,solid-state electrolytes were divided into five categories:solid inorganic electrolytes,solid polymer electrolytes,polymer/inorganic solid hybrid electrolytes,gel polymer electrolytes,and liquid–solid inorganic hybrid ***,the prospect of developing high performance solid-state electrolytes to improve the cycling stability of room temperature Na-S cells is envisaged.

关键词： sodium-sulfur batteries solid-state electrolytes ionic conductivity polysulfide shuttling interfacial compatibility

Novel rockburst prediction criterion with enhanced explainability employing CatBoost and nature-inspired metaheuristic technique

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Underground Space 2024年第6期19卷 101-118页

作者： Yingui qiu Jian Zhou School of Resources and Safety Engineering Central South UniversityChangsha 410083China

Rockburst is a major challenge to hard rock engineering at great *** and timely assessment of rockburst risk can avoid unnecessary casualties and property *** the existence of various methods for rockburst assessment,there remains an urgent need for a comprehensive and reliable criterion that is easy to both apply and *** a new rockburst criterion based on simple parameters can potentially fill this *** its advantages,this criterion can facilitate a more effective and efficient prediction of rockburst potential,thereby contributing significantly to enhancing safety *** this paper,combined with the internal and external factors of rockburst,four control variables(i.e.,integrity index,stress index,brittleness index,and elastic energy index)were selected to be incorporated into a comprehensive rockburstability index(RBSI).Based on 116 sets of rockburst cases,the rockburst potential was accurately quantified and predicted using the categorical boosting(CatBoost)model and the nature-inspired metaheuristic African vultures optimization algorithm(AVOA).In its performance validation,the criterion achieved the highest accuracy of 90.48%,verifying the reliability and effectiveness of the proposed RBSI ***,an interpretive method was applied to analyze the variable influence on the criterion,facilitating the explanation of predictions and the analysis of the formula’s robustness under different *** general,compared with existing criterion methods involving relevant indicators,the newly proposed RBSI criterion enhances the accuracy of rockburst potential prediction,and it can effectively and swiftly evaluate the preliminary risk of ***,a graphical user interface was developed to provide a clear visualization of the assessment of rockburst potential.

关键词： Rockburst criterion CatBoost Metaheuristic optimization Model interpretation Graphical user interface

Electrochemical conversion of organic compounds and inorganic small molecules

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Science China Chemistry 2024年第10期67卷 3223-3246页

作者： Weimei Zeng Youai qiu Department of Chemistry Nankai UniversityTianjin 300071China

Electrochemical synthesis presents a facile and sustainable strategy to produce valuable *** review summarizes the most recent advances in electrosynthesizing value-added compounds with inorganic small ***“small molecules”refers to a broad spectrum of chemicals,we mainly focus on the electrochemical conversion of CO_(2),H_(2)O/D_(2)O,NH_(3.and SO_(2)until March *** review intends to compare the results and display general trends throughout the field,with an emphasis on the substrate scope and mechanical ***,we propose several techniques and protocols that can enable a more fundamental understanding of the electrochemical reaction involving inorganic small molecules and help drive this methodology toward commercialization.

关键词： electrochemical synthesis inorganic small molecule organic synthesis carbon dioxide water

Enhanced service stability and thermoelectric performance in Cu_(2)−δSebased composites

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Science China Materials 2024年第7期67卷 2369-2370页

作者： Pengfei qiu Xun Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Thermoelectric(TE)materials can directly convert the industrial waste heat into useful electricity based on the Seebeck effect,providing a promising way to tackle the environmental pollution and global energy crisis[1].In the past several decades,many new high-performance TE materials have been discovered to enrich the TE *** them,Cu_(2)−δSe-based TE materials,which are in line with the“phonon-liquid electron-crystal”concept,have sparked widespread interest due to the high TE figure-of-merit(ZT)and the combination of elements that are nontoxic and earth-abundant[2].In 2012,Liu et al.[3.reported a ZT of 1.5 at 1000 K in the stoichiometric Cu_(2)*** alloying S at the Se-site,the ZT was enhanced to around 2.0 at 1000 K[4].Via incorporating carbon nanotubes,the ZT was further enhanced to 2.4 at 1000 K[5].Moreover,Yang et al.[6]and Zhou et al.[7]reported that the ZT of Cu_(2)Se/BiCuSeO composites can reach 2.7–2.8 around 1000 K.

关键词： composites BiCuSeO performance

直流偏磁对换相失败的影响机理及定量分析方法

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科学技术与工程 2016年第36期16卷 30-35页

作者：肖楚鹏金祖洋邱泽晶许朝阳丁胜南瑞集团公司(国网电力科学研究院) 南京211106 南瑞(武汉)电气设备与工程能效测评中心武汉430074 四川大学电气信息学院成都610065

针对直流输电系统故障恢复过程中出现的异常换相失败现象,理论分析了换流变压器直流偏磁、换相电压波形畸变、异常换相失败三者之间的关系。以换相电压波形畸变为桥梁,提出了直流偏磁对换相失败影响的定量分析方法。根据采用某特高压直... 详细信息

针对直流输电系统故障恢复过程中出现的异常换相失败现象,理论分析了换流变压器直流偏磁、换相电压波形畸变、异常换相失败三者之间的关系。以换相电压波形畸变为桥梁,提出了直流偏磁对换相失败影响的定量分析方法。根据采用某特高压直流输电系统实际工程参数建立的PSCAD/EMTDC仿真模型,应用所提方法分析了其故障恢复过程中异常换相失败,揭示了直流偏磁、电压畸变以及换相失败之间的内在联系并且量化了直流偏磁造成的换相电压谐波畸变对换相失败的影响,论证了方法的工程实用性。

关键词：直流偏磁换相电压畸变异常换相失败关系定量分析

y-Tuning: an efficient tuning paradigm for large-scale pre-trained models via label representation learning

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Frontiers of Computer Science 2024年第4期18卷 107-116页

作者： Yitao LIU Chenxin AN Xipeng qiu School of Computer Science Fudan UniversityShanghai 200433China

With current success of large-scale pre-trained models(PTMs),how efficiently adapting PTMs to downstream tasks has attracted tremendous attention,especially for PTMs with billions of *** work focuses on designing parameter-efficient tuning paradigms but needs to save and compute the gradient of the whole computational *** this paper,we propose y-Tuning,an efficient yet effective paradigm to adapt frozen large-scale PTMs to specific downstream tasks.y-Tuning learns dense representations for labels y defined in a given task and aligns them to fixed feature *** computing the gradients of text encoder at training phrase,y-Tuning is not only parameterefficient but also *** results show that for DeBERTaxxL with 1.6 billion parameters,y-Tuning achieves performance more than 96%of full fine-tuning on GLUE Benchmark with only 2%tunable parameters and much fewer training costs.

关键词： pre-trained model lightweight fine-tuning paradigms label representation

The First Five Years of a Phase Theory for Complex Systems and Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1728-1743页

作者： Dan Wang Wei Chen Li qiu Division of Decision and Control Systems KTH Royal Institute of TechnologyStockholm 10044Sweden Department of Mechanics and Engineering Science&the State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing 100871China Hong Kong University of Science and Technology Hong KongChinaand also with the Southern University of Science and TechnologyShenzhen 518055China

In this paper,we review the development of a phase theory for systems and networks in its first five years,represented by a trilogy:Matrix phases and their properties;The MIMO LTI system phase response,its physical interpretations,the small phase theorem,and the sectored real lemma;The synchronization of a multi-agent network using phase *** the end,we also summarize a list of ongoing research on the phase theory and speculate what will happen in the next five years.

关键词： Consensus and synchronization matrix phases multi-agent systems phase theory sectored real lemma small phase theorem.

Effect of Modulus Heterogeneity on the Equilibrium Shape and Stress Field ofαPrecipitate in Ti-6Al-4V

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 1017-1028页

作者： Di qiu Rongpei Shi Materials Genome Institute Shanghai UniversityShanghai200444China School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen518055China Shanghai Frontier Science Center of Mechanoinformatics Shanghai UniversityShanghai200444China Zhejiang Laboratory Hangzhou311100China

For media with inclusions(e.g.,precipitates,voids,reinforcements,and others),the difference in lattice parameter and the elastic modulus between the matrix and inclusions cause stress concentration at the *** stress fields depend on the inclusions’size,shape,and distribution and will respond instantly to the evolving *** study develops a phase-field model concerningmodulus *** effect of modulus heterogeneity on the growth process and equilibrium state of theαplate in Ti-6Al-4V during precipitation is ***αprecipitate exhibits strong anisotropy in shape upon cooling due to the interplay of the elastic strain and interfacial *** calculated orientation of the habit plane using the homogeneous modulus ofαphase shows the smallest deviation fromthat of the habit plane observed in the experiment,compared to the case where the homogeneous modulus ofβphase is *** addition,the equilibrium volume ofαphase within the systemusing homogeneousβmodulus exhibits the largest dependency on the applied *** stress fields across theα/βinterface are further calculated under the assumption of modulus heterogeneity and compared to those using homogeneous modulus of eitherαorβ*** study provides an essential theoretical basis for developing mechanics models concerning systems with heterogeneous structures.

关键词： Elastic heterogeneity habit plane stress field titanium phase-field simulation

An oscillation-free Hermite WENO scheme for hyperbolic conservation laws

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Science China Mathematics 2024年第2期67卷 431-454页

作者： Zhuang Zhao Jianxian qiu School of Mathematical Sciences and Institute of Natural Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen UniversityXiamen 361005China

In this paper, the sixth-order oscillation-free Hermite weighted essentially non-oscillatory (OFHWENO) scheme is proposed for hyperbolic conservation laws on structured meshes, where the zeroth- andfirst-order moments are the variables for the governing equations. The main difference from other HWENOschemes existing in the literature is that we add high-order numerical damping terms in the first-order momentequations to control spurious oscillations for the OF-HWENO scheme. The OF-HWENO scheme not only canachieve the designed optimal numerical order, but also can be easily implemented as we use only one set ofstencils in the reconstruction procedure and the same reconstructed polynomials are applied for the zeroth- andfirst-order moment equations. In order to obtain the adaptive order resolution when facing discontinuities, atransition polynomial is added in the reconstruction, where the associated linear weights can also be any positivenumbers as long as their summation equals one. In addition, the OF-HWENO scheme still keeps compactnessas only immediate neighbor values are needed in the space discretization. Some benchmark numerical tests areperformed to illustrate the high-order accuracy, high resolution and robustness of the proposed scheme.

关键词： Hermite WENO scheme hyperbolic conservation laws oscillation-free adaptive order discontinuous Galerkin method