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A review of data-driven whole-life state of health prediction for lithium-ion batteries:Data preprocessing,aging characteristics,algorithms,and future challenges
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作者 Yanxin Xie Shunli Wang +3 位作者 Gexiang Zhang Paul Takyi-Aninakwa Carlos Fernandez Frede Blaabjerg 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期630-649,I0013,共21页
Lithium-ion batteries are the preferred green energy storage method and are equipped with intelligent battery management systems(BMSs)that efficiently manage the batteries.This not only ensures the safety performance ... Lithium-ion batteries are the preferred green energy storage method and are equipped with intelligent battery management systems(BMSs)that efficiently manage the batteries.This not only ensures the safety performance of the batteries but also significantly improves their efficiency and reduces their damage rate.Throughout their whole life cycle,lithium-ion batteries undergo aging and performance degradation due to diverse external environments and irregular degradation of internal materials.This degradation is reflected in the state of health(SOH)assessment.Therefore,this review offers the first comprehensive analysis of battery SOH estimation strategies across the entire lifecycle over the past five years,highlighting common research focuses rooted in data-driven methods.It delves into various dimensions such as dataset integration and preprocessing,health feature parameter extraction,and the construction of SOH estimation models.These approaches unearth hidden insights within data,addressing the inherent tension between computational complexity and estimation accuracy.To enha nce support for in-vehicle implementation,cloud computing,and the echelon technologies of battery recycling,remanufacturing,and reuse,as well as to offer insights into these technologies,a segmented management approach will be introduced in the future.This will encompass source domain data processing,multi-feature factor reconfiguration,hybrid drive modeling,parameter correction mechanisms,and fulltime health management.Based on the best SOH estimation outcomes,health strategies tailored to different stages can be devised in the future,leading to the establishment of a comprehensive SOH assessment framework.This will mitigate cross-domain distribution disparities and facilitate adaptation to a broader array of dynamic operation protocols.This article reviews the current research landscape from four perspectives and discusses the challenges that lie ahead.Researchers and practitioners can gain a comprehensive understanding of battery SOH estimation methods,offering valuable insights for the development of advanced battery management systems and embedded application research. 展开更多
关键词 Lithium-ion batteries Whole life cycle aging mechanism Data-driven approach State of health Battery management system
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Effect of thermal-cooling cycle treatment on thermal expansion behavior of particulate reinforced aluminum matrix composites 被引量:5
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作者 陈国钦 修子扬 +2 位作者 杨文澍 姜龙涛 武高辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第11期2143-2147,共5页
Two micron SiC particles with angular and spherical shape and the sub-micron Al2O3 particles with spherical shape were introduced to reinforce 6061 aluminium by squeeze casting technology. Microstructures and effect o... Two micron SiC particles with angular and spherical shape and the sub-micron Al2O3 particles with spherical shape were introduced to reinforce 6061 aluminium by squeeze casting technology. Microstructures and effect of thermal-cooling cycle treatment (TCCT) on the thermal expansion behaviors of three composites were investigated. The results show that the composites are free of porosity and SiC/Al2O3 particles are distributed uniformly. Inflections at about 300℃ are observed in coefficient of thermal expansion (CTE) versus temperature curves of two SiCp/Al composites, and this characteristic is not affected by TCCT. The TCCT has significant effect on thermal expansion behavior of SiCp/Al composites and CTE of them after 3 cycles is lower than that of 1 or 5 cycles. However, no inflection is observed in Al2O3p/Al composite, while TCCT has effect on CTE of Al2O3p/Al composite. These results should be due to different relaxation behavior of internal stress in three composites. 展开更多
关键词 SiC aluminum matrix composite thermal expansion behavior thermal-cooling cycle treatment
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EFFECT OF DYNAMIC STRAIN AGING ON LOW CYCLE FATIGUE BEHAVIOUR OF 18-8 AUSTENITIC STAINLESS STEEL 被引量:2
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作者 PENG Kaiping CHEN Wenzhe OIAN Kuangwu Fuzhou University,Fuzhou,China teaching assistant,Department of Mechanical Engineering,Fuzhou University,Fuzhou 350002,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1993年第6期420-425,共6页
Studies were made of the symmetric tensile-compressive low cycle fatigue behaviour and the influence of dynamic strain aging(DSA)pre-treatment of 18-8 austenitic stainless steel. Within the testing amplitude range of ... Studies were made of the symmetric tensile-compressive low cycle fatigue behaviour and the influence of dynamic strain aging(DSA)pre-treatment of 18-8 austenitic stainless steel. Within the testing amplitude range of strain.±0.5 % to±1.5 %,the three processes of cyclic hardening,cyclic saturation and cyclic softening were observed.In the same amplitude of strain,the peak stress of the samples pre-treated by DSA is higher than that of solid-solu- tion and cold working pre-treatment,but no remarkable differences of the fatigue lives of them were found.TEM observation shows that the uniform and stable dislocation networks with high density form after DSA pre-treatment,which increases the cyclic peak stress.The cyclic softening results from the low dislocation density and elongated cell structure with low energy. 展开更多
关键词 18-8 austenitic stainless steel dynamic strain aging low cycle fatigue
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Effects of Aging Temperature on Microstructure and High Cycle Fatigue Performance of 7075 Aluminum Alloy 被引量:2
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作者 杨大炼 刘义伦 +3 位作者 LI Songbai MA Liyong LIU Chi YI Jiuhuo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第3期677-684,共8页
The hardness, the tensile and the high-cycle fatigue(HCF) performances of 7075 aluminum alloy were investigated under temper T651, solution treated at 380 ℃ for 0.5 h and aged at different temperatures(150, 170, 1... The hardness, the tensile and the high-cycle fatigue(HCF) performances of 7075 aluminum alloy were investigated under temper T651, solution treated at 380 ℃ for 0.5 h and aged at different temperatures(150, 170, 190 ℃) for 10 hours. The optimal microstructures and the fatigue fracture surfaces were observed. The results show that the hardness and the tensile performances are at their optimum at T651, but the fatigue life is the shortest. The hardness and the elongation are the lowest after solution treatment. With the aging temperature increasing(150-190 ℃), the HCF is improved. The crack is initiated from the impurity particles on the subsurface. Treated at 170 ℃,the area of the quasi-cleavage plane and the width of parallel serrated sections of the crack propagation are the largest. With increasing aging temperature, the dimple size of finally fracture surfaces becomes larger and the depth deeper. 展开更多
关键词 creep aging forming(CAF) high cycle fatigue(HCF) microstructure 7075 aluminum alloy
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T6态热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金的低周疲劳行为
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作者 王莹 陈立佳 +2 位作者 周舸 张浩宇 张思倩 《沈阳工业大学学报》 CAS 北大核心 2024年第1期77-81,共5页
为了揭示经过T6处理的热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金在不同温度下的低周疲劳变形与断裂行为,对T6态热挤压合金进行了室温和200℃条件下的低周疲劳实验。结果表明:在室温和200℃下合金塑性应变幅与载荷反向周次之间服从Coff... 为了揭示经过T6处理的热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金在不同温度下的低周疲劳变形与断裂行为,对T6态热挤压合金进行了室温和200℃条件下的低周疲劳实验。结果表明:在室温和200℃下合金塑性应变幅与载荷反向周次之间服从Coffin-Manson公式,而弹性应变幅与载荷反向周次之间服从Basquin公式;合金在室温和200℃下低周疲劳变形时,在较低外加总应变幅下疲劳变形机制主要为平面滑移,而在较高外加总应变幅下疲劳变形机制主要为波状滑移;室温和200℃下合金的疲劳裂纹均萌生于疲劳试样表面并以穿晶方式扩展。 展开更多
关键词 AL-CU-MG-ag合金 T6处理 低周疲劳 循环硬化 循环稳定 疲劳寿命 变形机制 疲劳断裂
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Anti-cracking Property of EVA-modified Polypropylene Fiber-reinforced Concrete Under Thermal-cooling Cycling Curing 被引量:2
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作者 LIU Sifeng YANG Siyu +2 位作者 KONG Yaning WAN Tingting ZHAO Guorong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第5期1109-1118,共10页
In order to investigate the synergistic effect of re-dispersible powder-ethylene-vinyl acetate copolymer(EVA) and polypropylene fiber on the crack resistance of concrete under thermal fatigue loading, the compressive ... In order to investigate the synergistic effect of re-dispersible powder-ethylene-vinyl acetate copolymer(EVA) and polypropylene fiber on the crack resistance of concrete under thermal fatigue loading, the compressive strength, ultimate tensile strength, ultimate tensile strain and tensile modulus of elasticity were tested. In addition, ultrasonic method and scanning electron microscope analysis were used to explain the microstructure mechanism. The results show that polypropylene fiberreinforced concrete presents a better performance on crack resistance than ordinary concrete, and the synergism of EVA and polypropylene fiber can improve the anti-cracking ability of concrete further. 展开更多
关键词 anti-cracking property EVA-modified POLYPROPYLENE fiber-reinforced concrete thermal-cooling cyclING CURING
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Serrated magnetic properties in metallic glass by thermal cycle 被引量:1
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作者 李明哲 Sajad Sohrabi +3 位作者 丁大伟 董帮少 周少雄 汪卫华 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期271-274,共4页
Fe-based metallic glasses(MGs) with excellent soft magnetic properties are applicable in a wide range of electronic industry. We show that the cryogenic thermal cycle has a sensitive effect on soft magnetic properti... Fe-based metallic glasses(MGs) with excellent soft magnetic properties are applicable in a wide range of electronic industry. We show that the cryogenic thermal cycle has a sensitive effect on soft magnetic properties of Fe78Si9B13 glassy ribbon. The values of magnetic induction(or magnetic flux density) B and Hc coercivity c show fluctuation with increasing number of thermal cycles. This phenomenon is explained as thermal-cycle-induced stochastically structural aging or rejuvenation which randomly fluctuates magnetic anisotropy and, consequently, the magnetic induction and coercivity. Overall,increasing the number of thermal cycles improves the soft magnetic properties of the ribbon. The results could help understand the relationship between relaxation and magnetic property, and the thermal cycle could provide an effective approach to improving performances of metallic glasses in industry. 展开更多
关键词 amorphous soft magnetic materials REJUVENATION aging cryogenic thermal cycling
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Effect of Duty Cycle on Properties of Pulse-electro-deposited SnS:Ag Thin Films 被引量:1
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作者 LU Peimin1, JIA Hongjie1, YANG Yongli2, CHENG Shuying1 (1. College of Physics and Information Engineering, Institute of Micro-Nano Devices & Solar Cells, Fuzhou University, Fuzhou 350108, CHN 2. Key Laboratory of Analysis and Detection Technology for Food Safety of the Ministry of Education, Department of Chemistry, Fuzhou University, Fuzhou 350108, CHN) 《Semiconductor Photonics and Technology》 CAS 2010年第4期132-136,145,共6页
SnS∶Ag thin films were deposited on ITO glasses by pulse electro-deposition. By studying the effect of duty cycle on the properties of SnS∶Ag thin films, the optimum off-time(toff) is obtained to be 5 s, namely, the... SnS∶Ag thin films were deposited on ITO glasses by pulse electro-deposition. By studying the effect of duty cycle on the properties of SnS∶Ag thin films, the optimum off-time(toff) is obtained to be 5 s, namely, the optimal duty cycle is about 67%. The primary phase of SnS∶Ag films deposited on optimum parameters condition is SnS compound with good crystallization, and the films prefer to grow towards (111) plane. The films are dense, smooth and uniform with good microstructure, and the grains in the films are densely packed together, and their direct bandgap is about 1.40 eV. In addition, the bandgap of the films first rises and then drops with the increase of the duty cycle. 展开更多
关键词 DUTY cycle PULSE ELECTRODEPOSITION SnS∶ag thin films optical properties
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含Ag@Ni核壳结构粉体镍基复合涂层的多循环高温摩擦学性能
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作者 何乃如 方子文 +3 位作者 贾均红 杨杰 陈威 辛骅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第2期618-628,共11页
为了抑制Ag的扩散,采用化学镀方法制备Ag@Ni核壳结构粉体,并利用大气等离子喷涂技术制备NiCrAlY-Mo-Ag@Ni涂层,详细研究核壳结构设计对涂层在高温循环工况下的力学及摩擦学性能的影响。研究结果表明:Ag的核壳结构设计可以提高镍基涂层... 为了抑制Ag的扩散,采用化学镀方法制备Ag@Ni核壳结构粉体,并利用大气等离子喷涂技术制备NiCrAlY-Mo-Ag@Ni涂层,详细研究核壳结构设计对涂层在高温循环工况下的力学及摩擦学性能的影响。研究结果表明:Ag的核壳结构设计可以提高镍基涂层中Ag与NiCrAlY的界面结合强度,进而显著提高复合涂层的硬度。Ni覆层有效地抑制了Ag在高温摩擦过程中的扩散与耗散。800℃时NiCrAlY-Mo-Ag@Ni涂层的摩擦因数仅为0.25,磨损率仅为1×10^(-5)mm^(3)/(N·m),显著低于NiCrAlY-Mo-Ag涂层。同时,Ag的核壳结构设计使得涂层在高温多循环工况下始终保持良好的自润滑性和耐磨性。 展开更多
关键词 核壳结构 ag@Ni NI基复合涂层 摩擦学性能 高温热循环
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Parameter fitting of constitutive model and FEM analysis of solder joint thermal cycle reliability for lead-free solder Sn-3.5Ag 被引量:1
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作者 周萍 胡炳亭 +1 位作者 周孑民 杨莺 《Journal of Central South University》 SCIE EI CAS 2009年第3期339-343,共5页
The experimental tests of tensile for lead-flee solder Sn-3.5Ag were performed for the general work temperatures range from 11 to 90 ℃ and strain rate range from 5 × 10^-5 to 2 × 10^-2s^-1, and its stress--... The experimental tests of tensile for lead-flee solder Sn-3.5Ag were performed for the general work temperatures range from 11 to 90 ℃ and strain rate range from 5 × 10^-5 to 2 × 10^-2s^-1, and its stress--strain curves were compared to those of solder Sn-37Pb. The parameters in Anand model for solder Sn-3.5Ag were fitted based on experimental data and nonlinear fitting method, and its validity was checked by means of experimental data. Furthermore, the Anand model was used in the FEM analysis to evaluate solder joint thermal cycle reliability. The results show that solder Sn-3.5Ag has a better creep resistance than solder Sn-37Pb. The maximum stress is located at the upper right comer of the outmost solder joint from the symmetric center, and thermal fatigue life is predicted to be 3.796 × 10^4 cycles under the calculated conditions. 展开更多
关键词 lead free solder Sn-3.5ag alloy Sn-37Pb alloy constitutive model TENSILE FEM analysis thermal cycle reliability
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Analysis and Modeling of Calendar Aging and Cycle Aging of LiCoO_(2)/Graphite Cells
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作者 WANG Wei YUAN Baoqiang +1 位作者 SUN Qie WENNERSTEN Ronald 《Journal of Thermal Science》 SCIE EI CAS CSCD 2024年第3期1109-1118,共10页
Lithium-ion batteries are used in a wide range of applications.However,their cycle life suffers from the problem of capacity fade,which includes calendar and cycle aging.The effects of storage time,temperature and par... Lithium-ion batteries are used in a wide range of applications.However,their cycle life suffers from the problem of capacity fade,which includes calendar and cycle aging.The effects of storage time,temperature and partial charge-discharge cycling on the capacity fade of Li-ion batteries are investigated in this study.The calendar aging and cycle aging are presented based on the storage and cycling experiment on LiCoO_(2)/graphite cells under different storage temperature and different ranges of state of charge(SOC).Based on the measurement data,a one-component and a double-component aging model are presented to respectively describe the capacity fade caused by calendar and cycle aging.The calendar aging of LiCoO_(2)/graphite batteries is mainly affected by temperature and SOC during the storage.Mean SOC and change in SOC(ΔSOC)are the main factors affecting battery degradation during cycling operation. 展开更多
关键词 Lithium-ion battery LiCoO_(2)(LCO)/graphite calendar aging cycle aging lifetime model
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Asset Life Cycle Management in Finnish Water Utilities
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作者 Riikka P. Rajala Jarmo J. Hukka 《Journal of Water Resource and Protection》 2018年第6期587-595,共9页
The aim of this paper is to improve the water industry asset life cycle management framework towards more resilient water services in Finland. This paper is based on a literature study and a web-based semi-structured ... The aim of this paper is to improve the water industry asset life cycle management framework towards more resilient water services in Finland. This paper is based on a literature study and a web-based semi-structured thematic interview, in which the Finnish water utility managers identified the current status of their utilities’ asset management. The water services professionals are extremely worried that, by and large, water and sewage networks are still deteriorating, although the networks are nowadays rehabilitated more systematically. The survey reveals that although most of the surveyed utilities have adopted several processes and sub-processes of asset management, and a few utilities are even using some asset management guides, as a whole a strategic approach to and a comprehensive framework for optimized management of physical assets are not practiced. Therefore the development and introduction of specific asset management guidelines should be considered. In order to support successful usage of the asset management framework, the basic concepts and principles of engineering asset management should be included in educational and professional development programs, in particular at the university level. 展开更多
关键词 FINNISH WATER UTILITIES aging Infrastructure ASSET Life cycle MANagEMENT Framework Regulation and ENFORCEMENT
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Cell cycle and complement inhibitors may be specific for treatment of spinal cord injury in aged and young mice: transcriptomic analyses 被引量:5
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作者 Ming Hao Xin-ran Ji +5 位作者 Hua Chen Wei Zhang Li-cheng Zhang Li-hai Zhang Pei-fu Tang Ning Lu 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第3期518-527,共10页
Previous studies have reported age-specific pathological and functional outcomes in young and aged patients suffering spinal cord injury,but the mechanisms remain poorly understood. In this study, we examined mice wit... Previous studies have reported age-specific pathological and functional outcomes in young and aged patients suffering spinal cord injury,but the mechanisms remain poorly understood. In this study, we examined mice with spinal cord injury. Gene expression profiles from the Gene Expression Omnibus database (accession number GSE93561) were used, including spinal cord samples from 3 young injured mice (2–3-months old, induced by Impactor at Th9 level) and 3 control mice (2–3-months old, no treatment), as well as 2 aged injured mice (15–18-months old, induced by Impactor at Th9 level) and 2 control mice (15–18-months old, no treatment). Differentially expressed genes (DEGs) in spinal cord tissue from injured and control mice were identified using the Linear Models for Microarray data method,with a threshold of adjusted P 〈 0.05 and |logFC(fold change)| 〉 1.5. Protein–protein interaction networks were constructed using data from the STRING database, followed by module analysis by Cytoscape software to screen crucial genes. Kyoto encyclopedia of genes and genomes pathway and Gene Ontology enrichment analyses were performed to investigate the underlying functions of DEGs using Database for Annotation, Visualization and Integrated Discovery. Consequently, 1,604 and 1,153 DEGs were identified between injured and normal control mice in spinal cord tissue of aged and young mice, respectively. Furthermore, a Venn diagram showed that 960 DEGs were shared among aged and young mice, while 644 and 193 DEGs were specific to aged and young mice, respectively. Functional enrichment indicates that shared DEGs are involved in osteoclast differentiation, extracellular matrix–receptor interaction, nuclear factor-kappa B signaling pathway, and focal adhesion. Unique genes for aged and young injured groups were involved in the cell cycle (upregulation of PLK1) and complement (upregulation of C3) activation, respectively. These findings were confirmed by functional analysis of genes in modules (common, 4; aged, 2; young, 1) screened from protein–protein interaction networks. Accordingly, cell cycle and complement inhibitors may be specific treatments for spinal cord injury in aged and young mice, respectively. 展开更多
关键词 nerve regeneration spinal cord injury aged young TRANSCRIPTOME differentially expressed genes protein-protein interaction network function enrichment inflammation cell cycle COMPLEMENT neural regeneration
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Ex situ aging effect on sulfonated poly(ether ether ketone) membrane:Hydration-dehydration cycling and hydrothermal treatment
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作者 Seung-Young Choi Kyeong Sik Jin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期583-592,I0014,共11页
Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation ... Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation provides incremental proton conductivity to the membranes, whereas mechanical degradation drastically reduces device stability. On this basis, we describe here the effects of two different ex situ aging processes on sulfonated poly(ether ether ketone) membranes: hydrationdehydration cycling and prolonged hydrothermal treatment. Both aged membranes exhibited enhanced phase separation under the hydrated conditions, as characterized by small angle X-ray scattering.However, when the aged membranes were dried again, the nanostructure of the membranes aged via the hydration-dehydration cycling was recoverable, whereas that of the membranes aged via prolonged hydrothermal treatment was irreversible. Furthermore, the two differently aged membranes showed clear differences in thermal, mechanical, and electrochemical properties. Finally, we implemented both aged membranes in fuel cell application. The sample aged via hydration-dehydration cycling maintained its improved cell performance, whereas the sample aged via hydrothermal treatment showed drastically reduced cell performance after durability test for 50 h. 展开更多
关键词 Sulfonated poly(ether ether ketone) Humidity cycle test Ex situ aging Proton exchange membrane Fuel cell
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Influence of Ageing Heat Treatment on the High Cycle Fatigue of an 8090 Al-Li Alloy
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作者 Suhua AI Zhongguang WANG Yun ZHANG and Zhuangqi HU(State Key Laboratory for Fatigue and Fracture of Materials, Institute of Metal Research,Chinese Academy of Sciences, Shenyang 110015, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第6期445-450,共6页
Fatigue lives for the smooth and notched specimens of 8090 Al-Li alloy jn the different ageing conditions have been studied. For the smooth samples of 8090 alloy the artificial ageing results in an increase in fatigue... Fatigue lives for the smooth and notched specimens of 8090 Al-Li alloy jn the different ageing conditions have been studied. For the smooth samples of 8090 alloy the artificial ageing results in an increase in fatigue life in comparison with natural ageing. On the contrary, the notched specimens of 8090 alloy in the naturally aged condition show higher fatigue life than in the peak-aged. The exposure to either the peak-aged or naturally aged leads to superior fatigue properties of Al-Li alloy to the traditional high strength aluminum alloys of 7075 and 2024, especially in the latter aged condition. In all ageing conditions, i,e. naturally, under-, peak- and over-aged, the peak-aged 8090 alloy displays the highest fatigue life and the over-aged material has a minimum value at the same stress amplitude. The difference in fatigue life is mainly attributable to the size and distribution of strengthening precipitates as well as the wide of precipitate free zones (PFZ's) along grain boundaries. 展开更多
关键词 AL LI Influence of ageing Heat Treatment on the High cycle Fatigue of an 8090 Al-Li Alloy
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Spratlies Archipelago as the Australasian Tektite Impact Crater, Details of Formation &Richard Muller’s Dust Cloud Explanation for the Mid-Pleistocene Ice Age Cycle Transition 被引量:2
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作者 Hermann G. W. Burchard 《Open Journal of Geology》 2018年第1期1-8,共8页
Several significant events of a geological nature occurred approximately 800 ka before the present: (1) Australasian tektite fall (AA), (2) Brunhes-Matuyama geomagnetic reversal (BMR), (3) mid-Pleistocene changes in i... Several significant events of a geological nature occurred approximately 800 ka before the present: (1) Australasian tektite fall (AA), (2) Brunhes-Matuyama geomagnetic reversal (BMR), (3) mid-Pleistocene changes in ice age cycles. Add to these the undated fault system (4) in the South-West (SW) of the South China Sea (SCS). Here we offer a unified cause for all four of these in (5), an impact in the SCS of a large, massive cosmic object, likely a comet, obliquely coming from the SW at an extremely shallow angle, striking the Sunda shelf yet unexploded with the shock of its compressed air bow wave, and causing the continual shelf and slope to collapse, resulting in the fault system (4), then traveling almost tangentially to the surface, exploding at impact with the sea surface, ejecting the tektites (1), creating the formation underlying the later atolls of Spratlies Archipelago (6), Nansha Islands in Chinese, & causing the BMR (2). An explanation of event (3) was Richard Muller’s hypothesis of planet Earth passing through an interplanetary dust cloud periodically due to ecliptic precession. Here we hypothesize this cloud actually is a belt of Australasian tektites ejected into space at super-orbital velocities that Earth encounters about every 100 ka. 展开更多
关键词 Spratlies ARCHIPELagO Cosmic Object Impact Crater Australasian TEKTITES Brunhes-Matuyama Geomagnetic Reversal RICHARD Muller Dust Cloud Hypothesis Mid-Pleistocene Ice age cycle TRANSITION Google Earth High Resolution Update
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Effects of Freeze-Thaw Cycles on Physical and Mechanical Properties of Glulam Exposed to Outdoor Environment 被引量:3
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作者 Ruyuan Yang Haitao Li +4 位作者 Assima Dauletbek Mahmud Ashraf Rodolfo Lorenzo Youfu Sun Yuehong Wu 《Journal of Renewable Materials》 SCIE EI 2021年第7期1293-1307,共15页
This paper presents an experimental investigation to identify suitable indices to assess durability of glulam when subjected to freeze-thaw cycles in an exposed enviroenment.In this study,two types of glulam specimens... This paper presents an experimental investigation to identify suitable indices to assess durability of glulam when subjected to freeze-thaw cycles in an exposed enviroenment.In this study,two types of glulam specimens were tested for their performance when subjected to different levels of aging due to freezing and thawing.Effect of aging treatment on various parameters including thickness swelling rate,static bending strength,elastic modulus,shear strength,and peeling rate of adhesive layer were studied.Obtained results showed that freeze-thaw aging treatment did not affect the water-resistance of the specimens as measured by thickness swelling rate and had little effect on the dimensional stability of the material.However,the applied aging treatment weakened the bending resistance of the glulam specimens with more pronounced effects on on low-density wood.On the other hand,bond strength of high-density wood was relatively more affected due to the appliedfreeze-thaw cycles.For highdensity wood,it is suggested that the shear strength of the adhesive layer be taken as an important index to determine the durability of freeze-thaw cycles aging.For low-density wood,on the other hand,the static bending strength can be used as an index to determine the durability of glulam under freeze-thaw cycles aging. 展开更多
关键词 Freeze-thaw cycles structural glulam DURABILITY wood failure percentage accelerated aging
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Time series analysis of mantle cycles Part Ⅱ:The geologic record in zircons, large igneous provinces and mantle lithosphere 被引量:1
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作者 Kent C. Condie Stephen J. Puetz 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1327-1336,共10页
Igneous and detrital zircons have six major U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distribu... Igneous and detrital zircons have six major U/Pb isotopic age peaks in common(2700 Ma,1875 Ma.1045 Ma,625 Ma,265 Ma and 90 Ma).For igneous rocks,each age peak is comprised of subpeaks with distinct geographic distributions and a subpeak age range per age peak≤100 Myr.There are eight major LIP age peaks(found on≥10 crustal provinces)of which only four are in common to major detrital zircon age peaks(2715 Ma,1875 Ma,825 Ma,90 Ma).Of the whole-rock Re depletion ages,58%have correspo nding detrital zircon age peaks and 55%have corresponding LIP age peaks.Ten age pea ks are fou nd in common to igneous zircon,detrital zircon,LIP,and Re depletion age time series(3225 Ma,2875 Ma,2145 Ma,2085 Ma,1985 Ma,1785 Ma,1455 Ma,1175 Ma,825 Ma,and 90 Ma).and these are very robust peaks on a global scale as recorded in both crustal and mantle rocks.About 50%of the age peaks in each of these time series correspond to predicted peaks in a 94-Myr mantle cycle,including four of the ten peaks in common to all four time series(2875 Ma,1785 Ma,825 Ma and 90 Ma).Age peak widths and subpeak ranges per age peak suggest that mantle events responsible for age peaks are<100 Myr and many<50 Myr in duration.Age peak geographic distributions show three populations(≤1000 Ma,2500-1000 Ma,>2500 Ma),with the number of new provinces in which age peaks are represented decreasing with time within each population.The breaks between the populations(at 2.5 Ga and 1 Ga)fall near the onsets of two transitions in Earth history.The First Transition may represent a change from stagnant-lid tectonics into plate tectonics and the Second Transition,the onset of subduction of continental crust.The major factor controlling geographic distribution of age peaks is the changing locations of orogeny.Before^2 Ga,age subpeaks and peaks are housed in orogens within or around the edges of crustal provinces,mostly in accretionary orogens.but beginning at 1.9 Ga,collisional orogens become more important.The coincidence in duration between magmatic flare-ups in Phanerozoic arcs and duration of age subpeaks(10-30 Myr)is consiste nt with subpeaks representing periods of enhanced arcrelated magmatism.probably caused by increased subduction flux.The correlation of isotopic age peaks between time series supports a cause and effect relationship between mantle plume activity,continental magma production at convergent margins,and crustal deformation.Correlation of over half of the detrital zircon age peaks(and six of the nine major peaks)with Re depletion age peaks supports an interpretation of the zircon peaks as crustal growth rather than selective preservation peaks. 展开更多
关键词 Isotopic age PEAKS U/Pb zircon agES Re depletion agES Large IGNEOUS PROVINCES age peak correlation MANTLE cycles
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Second Law of Thermodynamics Formalism Applied to Finite Duration through Cycles of Living Dissipative Systems
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作者 Jorge Antonio Montemayor-Aldrete Pablo Ugalde-Vélez +2 位作者 Marcelo Del Castillo-Mussot Gerardo Jorge Vázquez Ernesto Federico Montemayor-Varela 《Advances in Aging Research》 2014年第5期368-379,共12页
A simple and general theory to describe basic irreversible thermodynamic aspects of aging in all dissipative living is presented. Any dissipative system during its operation continuously loses efficiency by the produc... A simple and general theory to describe basic irreversible thermodynamic aspects of aging in all dissipative living is presented. Any dissipative system during its operation continuously loses efficiency by the production of structural or functional defects because of the second law of thermodynamics. This continuous loss of efficiency occurs on all the dissipative systems through the realization of specific functional cycles, leading to a maximum action principle of any system involving the Planck’s constant during their total dissipative operation. We applied our theory to the calculation of men and women lifespans from basal metabolic rate per unit weight and to the calculation of a new aging parameter per cycle of some human organs or physiological functions. All microscopic theory of the aging of living beings should be consistent with the second law of the thermodynamics. In other words, the operation of the biological self-organized structures only implies a delay in which the dissipative biological systems outside of equilibrium approach inexorably to the thermodynamic equilibrium obeying the second law of the thermodynamics. 展开更多
关键词 aging Functional Damage ENTROPY Production Rate DISSIPATIVE Structures DISSIPATIVE cycles
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用于功率器件封装的新型Cu@Sn@Ag焊片性能
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作者 王天文 高卫民 +1 位作者 徐菊 徐红艳 《半导体技术》 CAS 北大核心 2023年第3期240-246,254,共8页
提出了一种用于焊接半导体芯片的新型焊接材料Cu@Sn@Ag焊片。对比分析了Cu@Sn@Ag焊片和商用PbSn5Ag2.5焊片焊层的孔隙率和力学性能,采用这两种焊片封装了110 A商用Si器件并对其进行了电学、热学性能和功率循环可靠性对比。结果表明:优... 提出了一种用于焊接半导体芯片的新型焊接材料Cu@Sn@Ag焊片。对比分析了Cu@Sn@Ag焊片和商用PbSn5Ag2.5焊片焊层的孔隙率和力学性能,采用这两种焊片封装了110 A商用Si器件并对其进行了电学、热学性能和功率循环可靠性对比。结果表明:优化后的Cu@Sn@Ag焊片孔隙率小于4%,焊层剪切强度平均值约为35 MPa;相应器件的最小热阻为0.18 K/W,且经过150000次的有源功率循环(温差为60℃)后正向压降增长率基本小于2%,Cu@Sn@Ag焊片的性能和器件功率循环可靠性高于商用PbSn5Ag2.5焊片。基于瞬态液相扩散焊接(TLPS)的Cu@Sn@Ag焊片可以实现高铅焊片的无铅化替代,是一种具有良好应用前景的耐高温芯片焊接材料。 展开更多
关键词 Cu@Sn@ag焊片 瞬态液相扩散焊接(TLPS) 功率器件 剪切强度 功率循环
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