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Journal of Materials Science & Technology 2019年第6期35卷 1099-1107页

作者： X.Y. Jiao J. Wang C.F. Liu Z.P. guo g.d. tong S.L. Ma Y. Bi Y.F. Zhang S.M. Xiong School of Materials Science and Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Automobile Safety and Energy Tsinghua University Beijing China China FAW Foundry Co. Ltd. Changchun 130011. China

The fracture behavior of high-pressure die-cast hypereutectic(HPdC) Al-Si alloys was investigated using a high-resolution laboratory CT and synchrotron X-ray tomography with a particular focus on the influence of HPdC microstructure. Results showed that microstructure of the alloy was mainly comprised of primary silicon particles(PSPs), Al dendrites, Cu-rich phases and pores. Most of the coarse PSPs, Cu-rich phases and pores were located in the center of the specimen. The rapid solidification of HPdC led to a heterogeneous microstructural feature. Elemental Cu was enriched in the frontiers of solid-liquid interface, causing the formation of large size dendritic arms. The pores were formed in the interdendrites which endured high stress intensity under high applied stress. Microcracks were originated from pores and further connected Cu-rich phases causing intergranular fracture. PSPs worked as obstacles causing piling-up dislocations in the phase interface. In the regions where large size of PSPs enriched in, PSPs ruptured rather than debonded from matrix, indicating transgranular fractures of PSPs. Microcracks originated around pores and PSPs tended to converge on the main cracks to decrease the energy required for crack propagation.

关键词： Hypereutectic Al-Si alloy Primary silicon particles Porosity Fracture morphology High pressure die casting

Advancements in Humanoid Robots: A Comprehensive Review and Future Prospects

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 301-328页

作者： Yuchuang tong Haotian Liu Zhengtao Zhang IEEE CAS Engineering Laboratory for Intelligent Industrial Vision Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

This paper provides a comprehensive review of the current status, advancements, and future prospects of humanoid robots, highlighting their significance in driving the evolution of next-generation industries. By analyzing various research endeavors and key technologies, encompassing ontology structure,control and decision-making, and perception and interaction, a holistic overview of the current state of humanoid robot research is presented. Furthermore, emerging challenges in the field are identified, emphasizing the necessity for a deeper understanding of biological motion mechanisms, improved structural design,enhanced material applications, advanced drive and control methods, and efficient energy utilization. The integration of bionics, brain-inspired intelligence, mechanics, and control is underscored as a promising.d.rection for the development of advanced humanoid robotic systems. This paper serves as an invaluable resource, offering insightful guidance to researchers in the field,while contributing to the ongoing evolution and potential of humanoid robots across diverse domains.

关键词： Future trends and challenges humanoid robots human-robot interaction key technologies potential applications

Quantum Tunneling Enhanced Hydrogen desorption from graphene Surface: Atomic versus Molecular Mechanism

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Chinese Physics Letters 2024年第8期41卷 58-68页

作者： Yangwu tong Yong Yang Science Island Branch of graduate School University of Science and Technology of ChinaHefei 230026China Key Lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China

We study the desorption mechanism of hydrogen isotopes from graphene surface using first-principles calculations,with focus on the effects of quantum *** low temperatures,quantum tunneling plays a dominant role in the desorption process of both hydrogen monomers and *** the case of dimer desorption,two types of mechanisms,namely the traditional one-step desorption in the form of molecules(molecular mechanism),and the two-step desorption in the form of individual atoms(atomic mechanism),are studied and *** the ortho-dimers,the dominant desorption mechanism is found to switch from the molecular mechanism to the atomic mechanism above a critical temperature,which is∼300K and 200K for H and d,respectively.

关键词： desorption quantum mechanism

Highly efficient and stable 2d/3d perovskite solar cells based on surface reconstruction and energy level alignment

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Science China Chemistry 2024年第9期67卷 3083-3090页

作者： Qiaohui Li Hang Liu tong Zhou Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science and TechnologyQingdao 266042China The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

Realizing simultaneous adjustment of energy levels and work functions in two-dimensional/three-dimensional(2d/3d)perovskite solar cells(PSCs)is a ***,a pseudohalide 3,5-bis(trifluoromethyl)benzylammonium tetrafluoroborate(TFPMABF_(4))was used to react with unreacted Pb I2on the surface of 3d bulky perovskite to form a mixed halide of 2d perovskite denoted(TF-PMA)_(2)FA_(2)Pb_(3)I_(8)(BF_(4))_(2).This novel 2d/3d perovskite enables the simultaneous adjustment of energy levels and work functions on the surface of active *** to the significantly enhanced quality of 2d/3d perovskite film,decreased surface defects and increased charge carrier lifetime,the 2d/3d PSCs exhibit an outstanding power conversion efficiency(PCE)of 25.15%and a high V_(OC)of 1.194 ***,2d/3d PSCs exhibit remarkable enhancements in environmental stability,unencapsulated devices retaining more than 90%of their initial PCE at 50%humidity for 2,280 h.

关键词： 2d/3d perovskite perovskite solar cells organic spacers energy levels alignment

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Optimization of Band gap of 1d Elastic Metamaterial Under Impact Load by Regulating Stiffness

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Acta Mechanica Solida Sinica 2024年第1期37卷 148-154页

作者： tong Li Xianlong Jin Yongqiang Li Peizhong Yang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiaotong UniversityShanghai 200240China College of Science Northeastern UniversityShenyang 110819China

designing materials that mitigate impacts effectively are crucial for protecting people and ***,a single-resonator metamaterial with negative mass characteristics is proposed for impact mitigation,and numerical analysis of wave propagation shows explicitly how the spring stiffness and number of unit cells influence that *** results show clearly that a metamaterial with differing microstructural stiffness is better at mitigating the effect of a shock wave than one with a unique ***,there is a critical number of unit cells beyond which the shock wave is not attenuated further,but the fabrication complexity *** the 40 groups of microstructural regions in this example,the attenuation effect no longer increases when there are more than 35 *** work offers guidance for microstructure designs in metamaterials and provides new ideas for using metamaterials to mitigate shock waves.

关键词： Elastic metamaterials Wave attenuation Stiffness Number of unit cells

Boundary Points,Minimal L^(2)Integrals and Concavity PropertyⅢ—Linearity on Riemann Surfaces and Fibrations over Open Riemann Surfaces

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2091-2152页

作者： Qi An gUAN Zhi tong MI Zheng YUAN School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044P.R.China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China

In this article,we consider a modified version of minimal L^(2) integrals on sublevel sets of plurisubharmonic functions related to modules at boundary points,and obtain a concavity property of the modified *** applications,we give characterizations for the concavity degenerating to linearity on open Riemann surfaces and on fibrations over open Riemann surfaces.

关键词： Minimal L^(2)integrals plurisubharmonic functions boundary points weakly pseudoconvex Kähler manifold

Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

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Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： Lei Wan Yizhou tong Xi Lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerg.d.as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

Optimal retrofitting scenarios of multi-objective energy-efficient historic building under different national goals integrating energy simulation,reduced order modelling and NSgA-II algorithm

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Building Simulation 2024年第6期17卷 933-954页

作者： Hailu Wei Yuanhao Jiao Zhe Wang Wei Wang tong Zhang School of Architecture Southeast UniversityNanjingJiangsu Province210096China Key Laboratory of Urban and Architectural Heritage Conservation(Southeast University) Ministry of EducationNanjingChina department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute FutianShenzhenChina

Retrofitting a historic building under different national goals involves multiple objectives,constraints,and numerous potential measures and packages,therefore it is time-consuming and challenging.d.ring the early design *** study introduces a systematic retrofitting approach that incorporates standard measures for the building envelope(walls,windows,roof),as well as the heating,cooling,and lighting *** retrofit objectives are delineated based on prevailing Chinese *** retrofit measures function as genes to optimize energy-savings,carbon emissions,and net present value(NPV)by employing a log-additive decomposition approach through energy simulation techniques and NSgA-II,yielding 185,163,and 8 ***,a weighted sum method is proposed to derive optimal solutions across multiple *** framework is applied to a courtyard building in Nanjing,China,and the outcomes of the implementation are scrutinized to ascertain the optimal retrofit package under various *** this retrofit,energy consumption can be diminished by up to 63.62%,resulting in an NPV growth of 151.84%,and maximum rate of 60.48%carbon *** three result values not only indicate that the optimal values are achieved in these three aspects of energy saving,carbon reduction and economy,but also show the possibility of possible equilibrium in this multi-objective optimization *** framework proposed in this study effectively addresses the multi-objective optimization challenge in building renovation by employing a reliable optimization algorithm with a computationally efficient reduced-order *** provides valuable insights and recommendations for optimizing energy retrofit strategies and meeting various performance objectives.

关键词： historic building energy-efficient retrofitting building energy simulation log-additive decomposition approach NSgA-II

Machine learning in metal-ion battery research: Advancing material prediction, characterization, and status evaluation

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Journal of Energy Chemistry 2024年第3期90卷 191-204,I0006页

作者： tong Yu Chunyang Wang Huicong Yang Feng Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina department of Physics and Astronomy University of California IrvineIrvineCA92697USA

Metal-ion batteries(MIBs),including alkali metal-ion(Li^(+),Na^(+),and K^(3)),multi-valent metal-ion(Zn^(2+),Mg^(2+),and Al^(3+)),metal-air,and metal-sulfur batteries,play an indispensable role in electrochemical energy ***,the performance of MIBs is significantly influenced by numerous variables,resulting in multi-dimensional and long-term challenges in the field of battery research and performance *** learning(ML),with its capability to solve intricate tasks and perform robust data processing,is now catalyzing a revolutionary transformation in the development of MIB materials and *** this review,we summarize the utilization of ML algorithms that have expedited research on MIBs over the past five *** present an extensive overview of existing algorithms,elucidating their details,advantages,and limitations in various applications,which encompass electrode screening,material property prediction,electrolyte formulation design,electrode material characterization,manufacturing parameter optimization,and real-time battery status ***,we propose potential solutions and future directions for the application of ML in advancing MIB development.

关键词： Metal-ion battery Machine learning Electrode materials Characterization Status evaluation

d-Orbital steered FeN_(4)moiety through N,S dual-site adjustation for zinc-air flow battery

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Journal of Energy Chemistry 2024年第5期92卷 8-15页

作者： Chunzhu Bao Mingwei tong Xueli Li Zhonghua Xiang State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

The implementation of pristine covalent organic polymer(CO_(2)P)with well-defined structure as air electrode may spark fresh vitality to rechargeable zinc-air flow batteries(ZAFBs),but it still remains challenges in synergistically regulating their electronic states and structural porosity for the great device ***,we conquer these issues by exploiting N and S co-doped graphene with COP rich in metal-ligand nitrogen to synergistically construct an effective catalyst for oxygen reduction reaction(ORR).Among them,the N and S co-doped sites with high electronegativity properties alter the number of electron occupations in the d orbital of the iron centre and form electron-transfer bridges,thereby boosting the selectivity of the ORR-catalysed four-electron ***,the introduction of COP materials aids the formation of pore interstices in the graphene lamellae,which both adequately expose the active sites and facilitate the transport of reactive *** from the synergistic effect,as-prepared catalyst exhibits excellent half-wave potentials(E_(1/2)=912 mV)and stability(merely 8.8%drop after a long-term durability test of 50000 s).Further,ZAFBs assembled with the N/Sg@CO_(2)P catalyst demonstrate exceptional power density(163.8 mW cm^(-2))and continuous charge and discharge for approximately 140 h at 10 mA cm^(-2),outperforming the noble-metal benchmarks.

关键词： Nitrogen/sulfurdual sites Metal-coordinated nitrogen sites Covalent organic polymer Oxygen reduction reaction Zn-airflow battery