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浅析奥斯汀的“performatives”发展及对翻译学的影响
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作者 任士明 《安徽广播电视大学学报》 2006年第1期93-97,共5页
作为言语行为的最重要的奠基人之一,奥斯汀(Austin)从最初提出“constatives”与“performatives”的区别到最终放弃两者的区别,并把所有话语(utterances)归入“performatives”。本文在探究这种转变的同时,进一步追溯“performatives... 作为言语行为的最重要的奠基人之一,奥斯汀(Austin)从最初提出“constatives”与“performatives”的区别到最终放弃两者的区别,并把所有话语(utterances)归入“performatives”。本文在探究这种转变的同时,进一步追溯“performatives”的来源,为“performatives”在国内译法进行正名,概述舍尔(Sear-le)对“performatives”的发展以及罗伯逊(Robinson)利用“performatives”理论在翻译领域的研究。因此,笔者在探讨中发现了该理论的应用价值及其对翻译学的影响。 展开更多
关键词 performatives 奥斯汀 翻译学
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Karma Chameleon: Performative Acts, Gender Constitution, and the Second British Invasion
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作者 Diego Santos Vieira de Jesus 《Journal of Philosophy Study》 2021年第1期56-60,共5页
The aim is to examine the performative acts and gender constitution in the context of the Second British Invasion.Despite the pervasive character of patriarchy and the prevalence of sexual difference as an operative c... The aim is to examine the performative acts and gender constitution in the context of the Second British Invasion.Despite the pervasive character of patriarchy and the prevalence of sexual difference as an operative culturaldistinction, gender was not passively scripted on the bodies of many British singers. The subversive performancesdid not exclude suffering and marginalization but simultaneously undermined compulsory coherence. 展开更多
关键词 performative acts GENDER Judith Butler the Second British Invasion United Kingdom United States 1980s
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Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei 被引量:1
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作者 Shicheng Su Nianqing Jin Xiaoli Wei 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期12-28,共17页
Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in... Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted. 展开更多
关键词 THINNING Understory light environment Phoebe bournei Photosynthetic performance Growth performance
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集中配筋连接预制剪力墙抗震性能试验研究
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作者 肖扬 卢谦 +3 位作者 罗小勇 陈林松 程俊峰 张璧玮 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期201-218,共18页
针对现有预制混凝土剪力墙接缝施工容错率低、混凝土现场浇筑作业量大和钢筋锚固过长等不足,提出一种使用超高性能混凝土(UHPC)的集中配筋连接预制剪力墙。通过对比1片现浇剪力墙试件、3片不同接缝形式的集中配筋连接预制剪力墙试件的... 针对现有预制混凝土剪力墙接缝施工容错率低、混凝土现场浇筑作业量大和钢筋锚固过长等不足,提出一种使用超高性能混凝土(UHPC)的集中配筋连接预制剪力墙。通过对比1片现浇剪力墙试件、3片不同接缝形式的集中配筋连接预制剪力墙试件的拟静力试验结果,揭示该类预制剪力墙的破坏规律和抗震性能、竖缝对墙体抗震性能的影响和连接钢筋的受力特点。采用ABAQUS软件对试件进行有限元模拟,分析轴压比和集中配筋率对试件抗震性能的影响。研究结果表明:预制试件与现浇试件具有相同的破坏规律,均为弯剪破坏;这2类试件的滞回曲线均较饱满,骨架曲线走势基本一致,耗能能力接近,且预制试件的最小承载力仅比现浇试件低5.6%,表明预制试件的抗震性能与现浇试件的抗震性能基本相同;竖缝对剪力墙承载力的影响较小,使剪力墙的延性和耗能能力有一定的削弱;不同竖缝形式预制墙的抗震性能相近但各有特点,竖缝形式预制墙采用UHPC出筋搭接具有更好的整体性,采用U形键槽的预制墙具有更大的刚度和更强的耗能能力;连接钢筋的应力分布具有典型受弯构件的特征;随着轴压比增加,模型的刚度和承载力不断增加,在轴压比从0.05增加到0.30时,最大的峰值荷载增幅发生在轴压比从0.05到0.10时,从承载力的提高、刚度、耗能和墙角抬高等方面考虑,试件的集中配筋率保持在90%~110%为宜。 展开更多
关键词 预制剪力墙 集中配筋 拟静力试验 UHPC(ultra-high performance concrete) 抗震性能
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Control Strategies for Digital Twin Systems
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作者 Guo-Ping Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期170-180,共11页
With the continuous breakthrough in information technology and its integration into practical applications, industrial digital twins are expected to accelerate their development in the near future. This paper studies ... With the continuous breakthrough in information technology and its integration into practical applications, industrial digital twins are expected to accelerate their development in the near future. This paper studies various control strategies for digital twin systems from the viewpoint of practical applications.To make full use of advantages of digital twins for control systems, an architecture of digital twin control systems, adaptive model tracking scheme, performance prediction scheme, performance retention scheme, and fault tolerant control scheme are proposed. Those schemes are detailed to deal with different issues on model tracking, performance prediction, performance retention, and fault tolerant control of digital twin systems. Also, the stability of digital twin control systems is analysed. The proposed schemes for digital twin control systems are illustrated by examples. 展开更多
关键词 Digital twin control systems fault tolerant control model tracking performance prediction performance retention
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Dietary supplementation of laminarin improves the reproductive performance of sows and the growth of suckling piglets
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作者 Pengguang Zhang Guoyuan Jiang +6 位作者 Chenghong Ma Yubo Wang Enfa Yan Linjuan He Jianxin Guo Xin Zhang Jingdong Yin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期329-343,共15页
Background Maternal nutrition is essential in keeping a highly efficient production system in the pig industry.Laminarin has been shown to improve antioxidant capacity,reduce the inflammatory response,and favor the ho... Background Maternal nutrition is essential in keeping a highly efficient production system in the pig industry.Laminarin has been shown to improve antioxidant capacity,reduce the inflammatory response,and favor the homeostasis of intestinal microbiota.However,the effect of dietary supplementation of laminarin on the reproductive performance of sows and the growth of suckling offspring remains unknown.Methods A total of 40 Landrace×Yorkshire multiparous sows on d 85 of gestation,similar in age,body weight(BW),parity and reproductive performance,were randomly divided into four dietary treatments with 10 sows per treatment,receiving a control diet(basal pregnancy or lactating diets)and a basal diet supplemented with 0.025%,0.05%and 0.10%laminarin,respectively.The experiment lasted from d 85 of gestation to d 21 of lactation.Results Laminarin supplementation linearly increased number born alive per litter(P=0.03),average daily feed intake(ADFI,P<0.01),and total milk yield of sows during the lactation of 1–21 d(P=0.02).Furthermore,maternal laminarin supplementation increased the average daily gain(ADG)of piglets while tending to reduce the culling and death rate before weaning.In addition,alterations to the composition of colostrum and milk,as well as to serum inflammatory cytokines and immunoglobulins of sows were observed.The fecal microbiota profile of sows supported the improvement of reproductive performance in sows and the growth performance in suckling offspring.Conclusions Dietary supplementation of laminarin during late pregnancy and lactation could significantly improve reproductive performance of sows and growth performance of piglets. 展开更多
关键词 Fecal microbiota LAMINARIN MILK PIGLETS Reproductive performance SOWS
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Recent progress in the research on magnesium and magnesium alloy foils:A short review
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作者 Qiuyan Shen Yongxing Ba +3 位作者 Peng Zhang Jiangfeng Song Bin Jiang Fusheng Pan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期842-854,共13页
Magnesium and magnesium alloy foils have great potential for application in battery anodes,electromagnetic shielding,optics and acoustics,and biology because of their excellent specific damping,internal dissipation co... Magnesium and magnesium alloy foils have great potential for application in battery anodes,electromagnetic shielding,optics and acoustics,and biology because of their excellent specific damping,internal dissipation coefficients,magnetic and electrical conductivities,as well as high theoretical specific capacity.However,magnesium alloys exhibit poor deformation ability due to their hexagonal close-packed crystal structure.Preparing magnesium and magnesium alloy foils with thicknesses of less than 0.1 mm is difficult because of surface oxidation and grain growth at high temperatures or severe anisotropy after cold rolling that leads to cracks.Numerous methods have been applied to prepare magnesium alloy foils.They include warm rolling,cold rolling,accumulative roll bonding,electric plastic rolling,and on-line heating rolling.Defects of magnesium and magnesium alloy foils during preparation,such as edge cracks and breakage,are important factors for consideration.Herein,the current status of the research on magnesium and magnesium alloy foils is summarized from the aspects of foil preparation,defect control,performance characterization,and application prospects.The advantages and disadvantages of different preparation methods and defect(edge cracks and breakage)mechanisms in the preparation of foils are identified. 展开更多
关键词 magnesium alloy foil ROLLING DEFECT performance application
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Increased number of symptoms during the acute phase of SARS-CoV-2 infection in athletes is associated with prolonged time to return to full sports performance—AWAREⅧ
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作者 Carolette Snyders Marlise Dyer +2 位作者 Nicola Sewry Esme Jordaan Martin Schwellnus 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第3期280-287,I0001,共9页
Purpose The aim of the study was to identify factors associated with prolonged time to return to full performance(RTFP)in athletes with recent severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.Metho... Purpose The aim of the study was to identify factors associated with prolonged time to return to full performance(RTFP)in athletes with recent severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.Methods Prospective cohort study with cross sectional analysis.A total of 84 athletes with confirmed SARS-CoV-2 infection assessed at a coronavirus disease 2019 recovery clinic gave a history of age,sex,type/level of sport,co-morbidities,pre-infection training hours,and 26 acute SARS-CoV-2 symptoms from 3 categories(“nose and throat”,“chest and neck”,and“whole body”/systemic).Data on days to RTFP were obtained by structured interviews.Factors associated with RTFP were demographics,sport participation,history of co-morbidities,pre-infection training history,and acute symptoms(type,number).Outcomes were:(a)days to RTFP(median,interquartile range(IQR))in asymptomatic(n=7)and symptomatic athletes(n=77),and(b)hazard ratios(HRs;95%confidence interval)for symptomatic athletes with vs.without a factor(univariate,multiple models).HR<1 was predictive of higher percentage chance of prolonged RTFP.Significance was p<0.05.Results Days to RTFP were 30 days(IQR:23–40)for asymptomatic and 64 days(IQR:42–91)for symptomatic participants(p>0.05).Factors associated with prolonged RTFP(univariate models)were:females(HR=0.57;p=0.014),endurance athletes(HR=0.41;p<0.0001),co-morbidity number(HR=0.75;p=0.001),and respiratory disease history(HR=0.54;p=0.026).In symptomatic athletes,prolonged RTFP(multiple models)was significantly associated with increased“chest and neck”(HR=0.85;p=0.017)and“nose and throat”(HR=0.84;p=0.013)symptoms,but the association was more profound between prolonged RFTP and increased total number of“all symptoms”(HR=0.91;p=0.001)and“whole body”/systemic(HR=0.82;p=0.007)symptoms.Conclusion A larger number of total symptoms and specifically“whole body”/systemic symptoms during the acute phase of SARS-CoV-2 infection in athletes is associated with prolonged RTFP. 展开更多
关键词 ATHLETES COVID-19 Performance Recovery Return to play
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Sleep-based neuronal oscillations as a physiological biomarker for Alzheimer's disease:is night time the right time?
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作者 Jonathan Witton Erica S.Brady Michael T.Craig 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1417-1418,共2页
Dementia is a devastating syndrome characterized by memory problems,confusion,and behavior changes that prevent people from performing everyday activities.It is the leading cause of dependency and disability amongst o... Dementia is a devastating syndrome characterized by memory problems,confusion,and behavior changes that prevent people from performing everyday activities.It is the leading cause of dependency and disability amongst older people,resulting in a global economic cost of ~$1.3 trillion.Around 58 million people are currently afflicted by dementia worldwide,with Alzheimer s disease(AD) causing most(60-70%) of these cases. 展开更多
关键词 ALZHEIMER EVERYDAY PERFORMING
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Effect of aspect ratio of elliptical stirred vessel on mixing time and flow field characteristics in the absence of baffles
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作者 Yuan Yao Peiqiao Liu +5 位作者 Qian Zhang Zequan Li Benjun Xi Changyuan Tao Yundong Wang Zuohua Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期63-74,共12页
Elliptical tanks were used as an alternative to circular tanks in order to improve mixing efficiency and reduce mixing time in unbaffled stirred tanks(USTs). Five different aspect ratios of elliptical vessels were des... Elliptical tanks were used as an alternative to circular tanks in order to improve mixing efficiency and reduce mixing time in unbaffled stirred tanks(USTs). Five different aspect ratios of elliptical vessels were designed to compare their mixing time and flow field. Computational fluid dynamics(CFD) simulations were performed using the k–ε model to calculate the mixing time and simulate turbulent flow field features, such as streamline shape, velocity distribution, vortex core region distribution, and turbulent kinetic energy(TKE) transfer. Visualization was also carried out to track the tinctorial evolution of the liquid phase. Results reveal that elliptical stirred tanks can significantly improve mixing performance in USTs. Specifically, the mixing time at an aspect ratio of 2.00 is only 45.3% of the one of a circular stirred tank. Furthermore, the secondary flow is strengthened and the vortex core region increases with the increase of aspect ratio. The axial velocity is more sensitive to the aspect ratio than the circumferential and radial velocity. Additionally, the TKE transfer in elliptical vessels is altered. These findings suggest that elliptical vessels offer a promising alternative to circular vessels for enhancing mixing performance in USTs. 展开更多
关键词 Mixing time CFD Stirred tank Secondary flow Mixing performance
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Effects of a school-based karate intervention on academic achievement,psychosocial functioning,and physical fitness:A multi-country cluster randomized controlled trial
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作者 Tania Pinto-Escalona Erica Gobbi +5 位作者 Pedro L.Valenzuela Simon J.Bennett Pierluigi Aschieri Manuel Martin-Loeches Antonio Paoli Oscar Martinez-de-Quel 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期90-98,共9页
Purpose:To examine the effects of a school-based karate intervention on academic achievement,psychosocial functioning,and physical fitness in children aged 7-8 years.Methods:Twenty schools in 5 different European coun... Purpose:To examine the effects of a school-based karate intervention on academic achievement,psychosocial functioning,and physical fitness in children aged 7-8 years.Methods:Twenty schools in 5 different European countries(2 second-grade classrooms per school)participated in a cluster randomized controlled trial(Sport at School trial).Participants were assigned to either a control group,which continued with their habitual physical education lessons,or to an intervention group,which replaced these lessons with a 1-year karate intervention(Karate Mind and Movement program).A total of 721 children(344 girls and 377 boys,7.4±0.5 years old,mean±SD)completed the study,of which 333 and 388 were assigned to the control group and intervention group,respectively.Outcomes included academic performance(average grade),psychosocial functioning(Strengths and Difficulties Questionnaire for parents),and different markers of physical fitness(cardiorespiratory fitness,balance,and flexibility).Results:The intervention provided small but significant benefits compared to the control group for academic achievement(d=0.16;p=0.003),conduct problems(d=-0.28;p=0.003),cardiorespiratory fitness(d=0.36;p<0.001),and balance(d=0.24;p=0.015).There was a trend towards significant benefits for flexibility(d=0.24;p=0.056).No significant benefits were observed for other variables,including psychosocial difficulties,emotional symptoms,hyperactivity/inattention,peer problems,or prosocial behaviour(all p>0.05).Conclusion:A 1-year school-based karate intervention was effective in improving academic achievement,conduct problems,and physical fitness in primary school children.The results support the inclusion of karate during physical education lessons. 展开更多
关键词 Academic performance Cardiorespiratory fitness Conduct problems KARATE Physical fitness
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The component-activity interrelationship of cobalt-based bifunctional electrocatalysts for overall water splitting:Strategies and performance
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作者 Mingjie Sun Riyue Ge +4 位作者 Sean Li Liming Dai Yiran Li Bin Liu Wenxian Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期453-474,共22页
Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysi... Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysis systems based on cobalt-based monofunctional hydrogen evolution reaction(HER)or oxygen evolution reaction(OER)catalysts have certain shortcomings in terms of resource utilization and universality.In contrast,cobalt-based bifunctional catalysts(CBCs)have attracted much attention in recent years for overall water splitting systems because of their practicality and reduced preparation cost of electrolyzer.This review aims to address the latest development in CBCs for total hydrolysis.The main modification strategies of CBCs are systematically classified in water electrolysis to provide an overview of how to regulate their morphology and electronic configuration.Then,the catalytic performance of CBCs in total-hydrolysis is summarized according to the types of cobalt-based phosphides,sulfides and oxides,and the mechanism of strengthened electrocatalytic ability is emphasized through combining experiments and theoretical calculations.Future efforts are finally suggested to focus on exploring the dynamic conversion of reaction intermediates and building near-industrial CBCs,designing advanced CBC materials through micro-modulation,and addressing commercial applications. 展开更多
关键词 COBALT Bifunctional electrocatalysis Water splitting Modification strategies Electrocatalytic performances
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Recent Progress in Improving Rate Performance of Cellulose-Derived Carbon Materials for Sodium-Ion Batteries
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作者 Fujuan Wang Tianyun Zhang +2 位作者 Tian Zhang Tianqi He Fen Ran 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期102-147,共46页
Cellulose-derived carbon is regarded as one of the most promising candidates for high-performance anode materials in sodium-ion batteries;however,its poor rate performance at higher current density remains a challenge... Cellulose-derived carbon is regarded as one of the most promising candidates for high-performance anode materials in sodium-ion batteries;however,its poor rate performance at higher current density remains a challenge to achieve high power density sodium-ion batteries.The present review comprehensively elucidates the structural characteristics of cellulose-based materials and cellulose-derived carbon materials,explores the limitations in enhancing rate performance arising from ion diffusion and electronic transfer at the level of cellulose-derived carbon materials,and proposes corresponding strategies to improve rate performance targeted at various precursors of cellulose-based materials.This review also presents an update on recent progress in cellulose-based materials and cellulose-derived carbon materials,with particular focuses on their molecular,crystalline,and aggregation structures.Furthermore,the relationship between storage sodium and rate performance the carbon materials is elucidated through theoretical calculations and characterization analyses.Finally,future perspectives regarding challenges and opportunities in the research field of cellulose-derived carbon anodes are briefly highlighted. 展开更多
关键词 CELLULOSE Hard carbon Anode materials Rate performance Sodium-ion batteries
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Effect of Molecular Weight on Thermoelectric Performance of P3HT Analogues with 2-Propoxyethyl Side Chains
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作者 董得福 WANG Wei +3 位作者 ZHAN Chun LI Chenglong ZHOU Qisheng 肖生强 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期268-281,共14页
By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared h... By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared herein in addition with step increment of about 7 kDa on numberaverage molecular weight(M_(n))from around 11 to 32 kDa(accordingly denoted as P11k,P18k,P25k,and P32k).When doped in film by FeCl_(3)at the optimized conditions,the maximum power factor(PF_(max))increases greatly from 4.3μW·m^(-1)·K^(-2)for P11k to 8.8μW·m^(-1)·K^(-2)for P18k,and further to 9.7μW·m^(-1)·K^(-2)for P25k,followed by a slight decrease to 9.2μW·m^(-1)·K^(-2)for P32k.The close Seebeck coefficients(S)at PF_(max)are observed in these doped polymer films due to their consistent frontier orbital energy levels and Fermi levels.The main contribution to this PF_(max)evolution thus comes from the corresponding conductivities(σ).Theσvariation of the doped films can be rationally correlated with their microstructure evolution. 展开更多
关键词 conjugated polymer molecular weight MICROSTRUCTURE thermoelectric performance
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Effects of Additives on the Microstructure and Tribology Performance of Ta-12W Alloy Micro-Arc Oxidation Coating
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作者 刘玲 HU Changgang +1 位作者 CHENG Wendong 刘兴泉 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期142-149,共8页
Oxide ceramic coatings were fabricated on tantalum alloys by micro-arc oxidation (MAO) to improve their hardness and tribological properties. The MAO coatings were manufactured in a mixed silicatephosphate electrolyte... Oxide ceramic coatings were fabricated on tantalum alloys by micro-arc oxidation (MAO) to improve their hardness and tribological properties. The MAO coatings were manufactured in a mixed silicatephosphate electrolyte containing NaF and/or EDTA (ethylene diamine tetraacetic acid). The surface morphology,cross-sectional view, chemical composition, hardness, and wear performance of the coatings were analysed. As revealed by the scanning electron microscopy, silica-rich nodules appear on the MAO coating obtained in the silicate-phosphate electrolyte, but the formation of nodules is inhibited with NaF and/or EDTA in the electrolyte.Also, they reduce the roughness and improve the compactness of the coatings, which are composed of Ta_(2)O_(5),(Ta, O), and TaO. A thick and hard coating is obtained in the NaF-containing electrolyte, and the tribology performance is effectively improved. With additives, the nodule structure is detached from the coating surface and dissolved in the electrolyte. By using NaF as an electrolyte additive, the abrasion performance of the MAO coating is enhanced by decreasing the nodule structure, increasing the size of micropores, and improving the coating hardness. 展开更多
关键词 micro-arc oxidation tantalum alloy ADDITIVES tribology performance
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Mechanical Behavior Based on Aggregates Microstructure of Ultra-high Performance Concrete
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作者 丁庆军 ZHOU Changsheng +4 位作者 张高展 GUO Hong LI Yang ZHANG Yongyuan GUO Kaizheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期673-681,共9页
We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic ... We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic modulus,ultrasonic pulse velocity,flexural strength,and toughness were investigated.Scanning electron microscopy and nanoindentation were also conducted to reveal the underlying mechanisms affecting macroscopic performance.Due to the superior interface bonding properties between mullite sand and matrix,the compressive strength and flexural toughness of UHPC have been significantly improved.Mullite sand and BCS aggregates have higher stiffness than quartz sand,contributing to the excellent elastic modulus exhibited by UHPC.The stiffness and volume of aggregates have a more significant impact on the elastic modulus of UHPC than interface performance,and the latter contributes more to the strength of UHPC.This study will provide a reference for developing UHPC with superior elastic modulus for structural engineering. 展开更多
关键词 ultra-high performance concrete mechanical properties fine aggregates MICROSTRUCTURE NANOINDENTATION
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Elliptical encirclement control capable of reinforcing performances for UAVs around a dynamic target
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作者 Fei Zhang Xingling Shao +1 位作者 Yi Xia Wendong Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期104-119,共16页
Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external disturbances.However,elliptical encirclement with a time-varying obs... Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external disturbances.However,elliptical encirclement with a time-varying observation radius,may permit a more flexible and high-efficacy enclosing solution,whilst the non-orthogonal property between axial and tangential speed components,non-ignorable environmental perturbations,and strict assignment requirements empower elliptical encircling control to be more challenging,and the relevant investigations are still open.Following this line,an appointed-time elliptical encircling control rule capable of reinforcing circumnavigation performances is developed to enable Unmanned Aerial Vehicles(UAVs)to move along a specified elliptical path within a predetermined reaching time.The remarkable merits of the designed strategy are that the relative distance controlling error can be guaranteed to evolve within specified regions with a designer-specified convergence behavior.Meanwhile,wind perturbations can be online counteracted based on an unknown system dynamics estimator(USDE)with only one regulating parameter and high computational efficiency.Lyapunov tool demonstrates that all involved error variables are ultimately limited,and simulations are implemented to confirm the usability of the suggested control algorithm. 展开更多
关键词 Elliptical encirclement Reinforced performances Wind perturbations UAVS
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Effect of crystal morphology of ultrahigh-nickel cathode materials on high temperature electrochemical stability of lithium ion batteries
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作者 Bi Luo Hui Li +5 位作者 Haoyu Qi Yun Liu Chuanbo Zheng Weitong Du Jiafeng Zhang Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期327-335,I0008,共10页
Higher nickel content endows Ni-rich cathode materials LiNi_(x)Co_yMn_(1-x-y)O_(2)(x>0.6)with higher specific capacity and high energy density,which is regarded as the most promising cathode materials for Li-ion ba... Higher nickel content endows Ni-rich cathode materials LiNi_(x)Co_yMn_(1-x-y)O_(2)(x>0.6)with higher specific capacity and high energy density,which is regarded as the most promising cathode materials for Li-ion batteries.However,the deterioration of structural stability hinders its practical application,especially under harsh working conditions such as high-temperature cycling.Given these circumstances,it becomes particularly critical to clarify the impact of the crystal morphology on the structure and high-temperature performance as for the ultrahigh-nickel cathodes.Herein,we conducted a comprehensive comparison in terms of microstructure,high-temperature long-cycle phase evolution,and high-temperature electrochemical stability,revealing the differences and the working mechanisms among polycrystalline(PC),single-crystalline(SC)and Al doped SC ultrahigh-nickel materials.The results show that the PC sample suffers a severe irreversible phase transition along with the appearance of microcracks,resulting a serious decay of both average voltage and the energy density.While the Al doped SC sample exhibits superior cycling stability with intact layered structure.In-situ XRD and intraparticle structural evolution characterization reveal that Al doping can significantly alleviate the irreversible phase transition,thus inhibiting microcracks generation and enabling enhanced structure.Specifically,it exhibits excellent cycling performance in pouch-type full-cell with a high capacity retention of 91.8%after 500 cycles at 55℃.This work promotes the fundamental understanding on the correlation between the crystalline morphology and high-temperature electrochemical stability and provides a guide for optimization the Ni-rich cathode materials. 展开更多
关键词 SINGLE-CRYSTALLINE Ultrahigh-nickel cathode High-temperature performance Phase evolution
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Microstructures and Properties of Biomedical Mg-Zn-Sn-Zr Rolled Alloys
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作者 周生刚 ZHANG Daxin +5 位作者 XU Yang DUAN Jihao LI Tao LIU Junfeng WANG Peng 曹勇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期766-773,共8页
The as-cast Mg-2.0Zn-1.5Sn-xZr(x=0,0.4,0.6,0.8,1.0 wt%)alloy was rolled with the pressure less than 5%each time.The microstructure,mechanical properties,corrosion properties and biocompatibility of the alloy were inve... The as-cast Mg-2.0Zn-1.5Sn-xZr(x=0,0.4,0.6,0.8,1.0 wt%)alloy was rolled with the pressure less than 5%each time.The microstructure,mechanical properties,corrosion properties and biocompatibility of the alloy were investigated.The microstructure of the alloy was observed and analyzed by scanning electron microscope,and the tensile test was carried out by universal tensile machine.The corrosion resistance of the alloy in Hank's solution was studied by hydrogen evolution experiment and electrochemical test,and the biocompatibility of the alloy was tested by L929 cells.The results show that Mg-2Zn-1.5Sn-xZr alloy has excellent mechanical properties.The elongation of Mg-2Zn-1.5Sn-xZr alloy decreases with the increase of Zr content,but the tensile strength first increases and then decreases with the increase of Zr concentration.When the Zr content is 0.8 wt%,the maximum tensile strength of the alloy is 235 MPa.The results of hydrogen evolution experiment and electrochemical analysis show that the corrosion resistance of the alloy is the best when the Zr content is 0.8 wt%,and all the five alloys have high biocompatibility.In conclusion,the rolled alloy has good properties and has broad application prospects in the field of biomaterials. 展开更多
关键词 magnesium alloy corrosion performance mechanical properties BIOCOMPATIBILITY
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Two-Way Neural Network Performance PredictionModel Based onKnowledge Evolution and Individual Similarity
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作者 Xinzheng Wang Bing Guo Yan Shen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1183-1206,共24页
Predicting students’academic achievements is an essential issue in education,which can benefit many stakeholders,for instance,students,teachers,managers,etc.Compared with online courses such asMOOCs,students’academi... Predicting students’academic achievements is an essential issue in education,which can benefit many stakeholders,for instance,students,teachers,managers,etc.Compared with online courses such asMOOCs,students’academicrelateddata in the face-to-face physical teaching environment is usually sparsity,and the sample size is relativelysmall.It makes building models to predict students’performance accurately in such an environment even morechallenging.This paper proposes a Two-WayNeuralNetwork(TWNN)model based on the bidirectional recurrentneural network and graph neural network to predict students’next semester’s course performance using only theirprevious course achievements.Extensive experiments on a real dataset show that our model performs better thanthe baselines in many indicators. 展开更多
关键词 COMPUTER EDUCATION performance prediction deep learning
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