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Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： Fan YANG Zhaoyang MA Xingming guo shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric s.udies. A new way that can regulate the bandgap is revealed by s.udying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

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Glass-forming ability, phase formation and mechanical properties of glass-forming Cu-Hf-Zr alloys

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Progress in Natural science:Materials International 2019年第5期29卷 576-581页

作者： K.Kosiba Kaikai song u.Kühn gang Wang s.Pauly Leibniz IFW Dresden Institute for Complex Materials school of Mechanical Electrical & Information Engineering Shandong University (Weihai) Laboratory for Microstructures Institute of Materials Shanghai University

The influence of Hf additions on the glass-forming ability（GFA）,phase formation and mechanical properties of Cu;Hf;Zr;（x=2,5,10,20 at.%）alloys has been systematically *** report on a distinct correlation between phase formation and GFA of Cu;Zr;-based *** additions of Hf reduce the thermal stability of the high-temperature B2Cu（Hf,Zr）phase,while the thermal stability of the corresponding undercooled melt is *** GFA of these alloy series gradually raises.up to 10 at.%Hf,whereas at 20 at.%Hf,the GFA is drastically lowered,since the B2Cu（Hf,Zr）phase becomes.unstable and the precipitation of the lowtemperature equilibrium phases is *** interrelation determines the microstructure and results in the formation of Cu-Hf-Zr-based bulk metallic glass *** composites not only show appreciable macroscopic plastic strain,but also high yield strength.

关键词： Metallic glasses Glass-forming ability Composites Continuous cooling transformation (CCT) diagram Mechanical properties

Mechanical Properties of Formamidinium Halide Perovskites FABX_3(FA=CH(NH_2)_2; B=Pb, sn; X=Br, I) by First-Principles Calculations

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Chinese Physics Letters 2019年第5期36卷 44-48页

作者： Lei guo gang Tang Jiawang Hong school of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081

The mechanical properties of formamidinium halide perovskites FABX_3(FA=CH(NH_2)_2; B=Pb, sn; X=Br, I)are systematically investigated using first-principles calculations. Our results reveal that FABX_3 perovskites possess excellent mechanical flexibility, ductility and strong anisotropy. We shows that the planar organic cation FA+ has an important effect on the mechanical properties of FABX3 perovskites. In addition, our results indicate that (i) the moduli(bulk modulus B, Young's modulus E, and shear modulus G) of FABBr_3 are larger than those of FABI_3 for the same B atom, and (ii) the moduli of FAPbX_3 are larger than those of FAsnX_3 for the same halide atom. The reason for the two trends is demonstrated by carefully analyzing the bond strength between B and X atoms based on the projected crystal orbital Hamilton population method.

关键词： FA=CH sn Mechanical Properties of Formamidinium Halide Perovskites FABX3 by First-Principles Calculations B FA CH

INTERMETALLIC ALLOYs AND COMPOsITEs FOR THE 21sT CENTuRY: A BAsIC ENERGY sCIENCEs PROGRAM OF THE u. s. DEPARTMENT OF ENERGY

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中国有色金属学会会刊：英文版 1999年第S1期9卷 355-363页

作者： Alan L. Dragoo Division of Materials sciences, Office of Basic Energy sciences, u.s.Department of Energy, Germantown, MD 2087-1290, u.s.A.

Progress has been made in intermetallic alloys over the past decade and a half, but intermetallics remain a relatively unexplored class of materials for energy applications. Hence, they offer considerable opportunities both for scientific research on fundamental structural property processing relationships and for technological development. The Department of Energy supports a program of scientific research on intermetallic alloys such as the nickel and iron aluminides and is establishing new research efforts in silicides and Laves phases through the program of the Division of Materials sciences, of the Office of Basic Energy sciences. Areas of research include theory and materials simulation, microalloying, high resolution sudies of structure and composition, mechanical properties, point defects and dislocation mechanics, phase transformations, and processing. Research is conducted through programs at the Department of Energy National Laboratories and through grants to academic and industrial *** results from Division of Materials sciences programs have provided the basis and transportation. In addition, a cooperative effort between research groups has been established as a project on intermetallic materials.under the Center of Excellence in synthesis and Processing of Advanced Materials.

关键词： intermetallics energy applications nickel aluminides iron aluminides silicides Laves phases

u.s. Department of Energy Research in Intermetallic Alloys and Composites

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Acta Metallurgica sinica(English Letters) 1995年第Z1期8卷 615-624页

作者： Alan L. Dragoo (Division of Materials sciences Office of Basic Energy sciences.u.s.Department of Energy Washington, D.C.20585) u.s.A.

The program of the Division of Materials sciences *** materials will be surveyed. This program is carried out at Department of Energy National Laboratories and at u.s. universities. Areas of research include theory and material simulation, microalloying, high resolution s.udies of structure and composition, mechanical properties, point defects and dislocation mechanics, phase transformations, and processing. Finally, general considerations will be dis.ussed for the future program.

关键词： Department of Energy Research in Intermetallic Alloys and Composites

Identification of Antarctic minke and killer whales with passive acoustic monitoring in Prydz Bay, Antarctica

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Journal of Oceanology and Limnology 2022年第2期40卷 485-495页

作者： Ying JIANG Lian-gang LÜ Zongwei LIu Chunmei YANG Jingsong guo First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Marine science and Numerical Modeling Ministry of Natural ResourcesQingdao 266061China

Although four species of odontocete and four species of baleen whale have been recorded in Prydz Bay,their vocalizations have been rarely *** vocalizations were recorded during March 2017 in Prydz Bay,***-duck s.unds,downsweeps,inverted“u”shape signals,whistles,pulsed s.unds,and broadband clicks were ***-duck s.unds and downsweeps were associated with Antarctic minke whales(Balaenoptera bonaerensis)based on visual *** between inverted“u”shape signals,biphonic calls,and clicks with vocalizations previously described for killer whales(Orcinus orca)lead us believe the presence of Antarctic killer *** to s.und structures,signal characteristics,and recording location,Antarctic type C killer whales were the most probable candidates to produce these detected *** represent the fi rst detection of inverted“u”shape signals in Antarctic waters,and the fi rst report of Antarctic killer whale in Prydz Bay based on passive acoustic *** co-existence of Antarctic minke and killer whales may imply that minke whales can detect diff erences between the s.unds of mammal-eating and fi sh-eating killer *** descriptions of these underwater vocalizations contribute to the limited body of information regarding the distribution and acoustic behavior of cetaceans in Prydz Bay.

关键词： passive acoustic monitoring inverted“u”shaped signal killer whale Antarctic minke whales Prydz Bay type C

Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator

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Nano-Micro Letters 2025年第1期17卷 378-403页

作者： Bin Xie Yuanhui guo Yun Chen Hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma Xin Chen Chingping Wong state Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China school of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006People’s Republic of China school of Materials science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation *** nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this *** the core component of TENG,the choice of electrode materials significantly affects its *** metal electrode materials often suffer from problems such as durability,which limits the further application of ***,as a novel electrode material,shows excellent prospects for application in TENG owing to its.unique structure and excellent electrical *** review systematically summarizes the recent research progress and application prospects of TENGs based on graphene *** precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are *** addition,the future development of graphene electrode-based TENGs is also prospectively dis.ussed,aiming to promote the continuous advancement of graphene electrode-based TENGs.

关键词： Triboelectric nanogenerator Precision processing Graphene electrode self-powered sensor

serverless distributed learning for smart grid analytics

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Chinese Physics B 2021年第8期30卷 558-565页

作者： gang Huang Chao Wu Yifan Hu Chuangxin guo Zhejiang Lab Hangzhou 311121China school of Public Affairs Zhejiang UniversityHangzhou 310058China Polytechnic Institute Zhejiang UniversityHangzhou 310015China College of Electrical Engineering Zhejiang UniversityHangzhou 310027China

The digitization,informatization,and intelligentization of physical systems require strong support from big data ***,due to restrictions on data security and privacy and concerns about the cost of big data collection,transmission,and storage,it is difficult to do data aggregation in real-world power systems,which directly retards the effective implementation of smart grid *** learning,an advanced distributed learning method proposed by Google,seems a promising solution to the above ***,it relies on a server node to complete model aggregation and the framework is limited to scenarios where data are independent and identically ***,we here propose a serverless distributed learning platform based on blockchain to solve the above two *** the proposed platform,the task of machine learning is performed according to smart contracts,and encrypted models are aggregated via a mechanism of knowledge *** this proposed method,a server node is no longer required and the learning ability is no longer limited to independent and identically distributed *** on a public electrical grid dataset will verify the effectiveness of the proposed approach.

关键词： smart grid physical system distributed learning artificial intelligence

simulation of Climate Negotiation strategies between China and the u.s. Based on Game Theory

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Advances in Climate Change Research 2014年第1期5卷 34-40页

作者： JIN Zhu-gang CAI Wen-Jia WANG Can Center for Earth system science Tsinghua University school of Environment Tsinghua University

Consensus and disagreements between China and the u.s. are the key factors influencing the direction that global climate negotiation is heading for. By taking into account the uncertainties of temperature increment and its impact on GDP growth, together with the positive, negative and spillover effects of climate change investment on utility, a strategic simulation model including China and the u.s. is developed. Based on utility and game theory, a sensitivity analysis is conducted. The results show that the first-mover disadvantage exists in the game, and the scale of each country＇s climate change investment under non-cooperative win-win basis for global cooperation, the technology transfer and funding to China scenario is too small to ensure the 2℃ simulation results also indicate that it target. To guarantee the stability and makes sense to assist and compensate

关键词： climate negotiation utility game theory strategy