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Bioinspired Passive Tactile Sensors Enabled by Reversible Polarization of Conjugated Polymers
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作者 Feng He Sitong Chen +3 位作者 Ruili Zhou Hanyu Diao Yangyang Han Xiaodong Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期361-377,共17页
Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors c... Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static stimuli.Here,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic stimuli.Specifically,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential differences.The controllable and reversible polarization process of the conjugated polymers is fully in situ characterized.Then,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference outputs.Compared with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior bio-friendliness.As demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning algorithms.This tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins. 展开更多
关键词 passive tactile sensors Reversible polarization of conjugated polymers Tactile perception Machine learning algorithm Object recognition
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Passive activity enhances residual control ability in patients with complete spinal cord injury
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作者 Yanqing Xiao Mingming Gao +6 位作者 Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2337-2347,共11页
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these... Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury. 展开更多
关键词 complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task
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Contrastive Analysis on Unmarkedness of English and Chinese Passives from the Perspective of Markedness Theory
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作者 李雨霏 《海外英语》 2018年第19期233-237,共5页
Markedness refers to the asymmetric phenomenon in a linguistic category. Unmarked item, compared with marked item,is more natural, more neutral, more fundamental, and has higher using frequency and wider distribution.... Markedness refers to the asymmetric phenomenon in a linguistic category. Unmarked item, compared with marked item,is more natural, more neutral, more fundamental, and has higher using frequency and wider distribution. From the perspective of markedness theory, the study, collecting 86 English passives and 85 Chinese passives(including 35 notional passives and 50 Beisentences), contrastively analyzes the unmarkedness of English and Chinese passives from the aspects of patient animacy, emotional color, and tense through example-illustration and description. The analysis shows that the unmarkedness of English and Chinese passives has different expressions in the three aspects. Inanimate patient has stronger unmarkedness in both English and Chinese passives, for it is more frequently-used than animate patient. According to people's cognition and language using habits, the emotional color of English passives and Chinese notional passives is neutral in most cases, so the neutral emotional color is unmarked.But in Chinese Bei-sentences, negative emotional color has stronger unmarkedness. As for the tense expression, English passives have wider distributions in time span and simpler structure than Chinese passives. Thus, English passives possess stronger unmarkedness in the light of tense. According to the analysis, the study proposes feasible advice for second language acquisition and translation. 展开更多
关键词 MARKEDNESS THEORY unmarkedness ENGLISH and Chinese passives CONTRASTIVE analysis
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Low-energy-consumption temperature swing system for CO_(2) capture by combining passive radiative cooling and solar heating 被引量:2
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作者 Ying-Xi Dang Peng Tan +3 位作者 Bin Hu Chen Gu Xiao-Qin Liu Lin-Bing Sun 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期507-515,共9页
Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative coo... Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption. 展开更多
关键词 CO_(2)capture Solar heating passive radiative cooling Temperature swing adsorption
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In-situ interfacial passivation and self-adaptability synergistically stabilizing all-solid-state lithium metal batteries 被引量:1
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作者 Huanhui Chen Xing Cao +6 位作者 Moujie Huang Xiangzhong Ren Yubin Zhao Liang Yu Ya Liu Liubiao Zhong Yejun Qiu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期282-292,I0007,共12页
The function of solid electrolytes and the composition of solid electrolyte interphase(SEI)are highly significant for inhibiting the growth of Li dendrites.Herein,we report an in-situ interfacial passivation combined ... The function of solid electrolytes and the composition of solid electrolyte interphase(SEI)are highly significant for inhibiting the growth of Li dendrites.Herein,we report an in-situ interfacial passivation combined with self-adaptability strategy to reinforce Li_(0.33)La_(0.557)TiO_(3)(LLTO)-based solid-state batteries.Specifically,a functional SEI enriched with LiF/Li_(3)PO_(4) is formed by in-situ electrochemical conversion,which is greatly beneficial to improving interface compatibility and enhancing ion transport.While the polarized dielectric BaTiO_(3)-polyamic acid(BTO-PAA,BP)film greatly improves the Li-ion transport kinetics and homogenizes the Li deposition.As expected,the resulting electrolyte offers considerable ionic conductivity at room temperature(4.3 x 10~(-4)S cm^(-1))and appreciable electrochemical decomposition voltage(5.23 V)after electrochemical passivation.For Li-LiFePO_(4) batteries,it shows a high specific capacity of 153 mA h g^(-1)at 0.2C after 100 cycles and a long-term durability of 115 mA h g^(-1)at 1.0 C after 800 cycles.Additionally,a stable Li plating/stripping can be achieved for more than 900 h at 0.5 mA cm^(-2).The stabilization mechanisms are elucidated by ex-situ XRD,ex-situ XPS,and ex-situ FTIR techniques,and the corresponding results reveal that the interfacial passivation combined with polarization effect is an effective strategy for improving the electrochemical performance.The present study provides a deeper insight into the dynamic adjustment of electrode-electrolyte interfacial for solid-state lithium batteries. 展开更多
关键词 Solid-state lithium batteries Composite solid electrolyte In-situ polymerization Interfacial passivation layer Self-adaptability
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A Comparison Study on the Passives Used by Natives Based on BNC Corpus
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作者 张艺敏 《海外英语》 2015年第20期209-210,共2页
With the development of computer science, corpus linguistics emerges as the times require. Since 1980 s, scholars at home and abroad have been committed to the construction and exploration of corpus, and have started ... With the development of computer science, corpus linguistics emerges as the times require. Since 1980 s, scholars at home and abroad have been committed to the construction and exploration of corpus, and have started a new era of corpus. Corpus can be seen as a storehouse to deposit the linguistic materials. It is a database, a scientifically organized collection of linguistic materials. In the language application, those linguistic materials can be both written and oral, are produced in a natural way. These raw materials are used to observe and grasp language facts, which are regarded as the first-hand data for the analysis and research of language rules. In this study, the author intends to achieve two main aims. The first is to investigate whether there are some differences in using the passives by native speakers when they write and speak, and whether such differences are statistically significant. The second is to investigate whether there are some differences in using the passives in native speakers' formal writings and informal writings, and whether such differences are statistically significant. 展开更多
关键词 CORPUS LINGUISTICS passives SIGNIFICANT DIFFERENCES
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The Meta-function Interpretation of the Use of Passives in English Academic Paper
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作者 王昕珏 《海外英语》 2013年第9X期154-155,共2页
Passive voice is a common phenomenon in English academic papers, which is consistent with the academic stylistic and linguistic characteristics of academic papers. Based upon Halliday's meta-function, the present ... Passive voice is a common phenomenon in English academic papers, which is consistent with the academic stylistic and linguistic characteristics of academic papers. Based upon Halliday's meta-function, the present paper explores the significance and function of the passives used in academic papers. The purpose is to facilitate English learners'understanding of the passives used in academic papers, thereby improving the quality of the papers. 展开更多
关键词 passive VOICE ENGLISH ACADEMIC PAPERS meta-functio
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Enhancing the Performance of Perovskite Light-Emitting Diodes via Synergistic Effect of Defect Passivation and Dielectric Screening
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作者 Xuanchi Yu Jia Guo +11 位作者 Yulin Mao Chengwei Shan Fengshou Tian Bingheng Meng Zhaojin Wang Tianqi Zhang Aung Ko Ko Kyaw Shuming Chen Xiaowei Sun Kai Wang Rui Chen Guichuan Xing 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期244-256,共13页
Metal halide perovskites,particularly the quasi-two-dimensional perovskite subclass,have exhibited considerable potential for next-generation electroluminescent materials for lighting and display.Nevertheless,the pres... Metal halide perovskites,particularly the quasi-two-dimensional perovskite subclass,have exhibited considerable potential for next-generation electroluminescent materials for lighting and display.Nevertheless,the presence of defects within these perovskites has a substantial influence on the emission efficiency and durability of the devices.In this study,we revealed a synergistic passivation mechanism on perovskite films by using a dual-functional compound of potassium bromide.The dual functional potassium bromide on the one hand can passivate the defects of halide vacancies with bromine anions and,on the other hand,can screen the charged defects at the grain boundaries with potassium cations.This approach effectively reduces the probability of carriers quenching resulting from charged defects capture and consequently enhances the radiative recombination efficiency of perovskite thin films,leading to a significant enhancement of photoluminescence quantum yield to near-unity values(95%).Meanwhile,the potassium bromide treatment promoted the growth of homogeneous and smooth film,facilitating the charge carrier injection in the devices.Consequently,the perovskite light-emitting diodes based on this strategy achieve a maximum external quantum efficiency of~21%and maximum luminance of~60,000 cd m^(-2).This work provides a deeper insight into the passivation mechanism of ionic compound additives in perovskite with the solution method. 展开更多
关键词 Synergistic passivation strategy Defects passivation Dielectric screening Perovskite light-emitting diodes
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Bifunctional passivation by lewis-base molecules for efficient printable mesoscopic perovskite solar cells
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作者 Hang Yang Jianhong Zhao +8 位作者 Xiaodong Ren Tong Zhou Henbing Zhang Weilong Zhang Jin Zhang Guangzhi Hu Yuming Zhang Wen-Hua Zhang Qingju Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期177-184,共8页
Printable mesoscopic perovskite solar cells(PM-PSCs)possess notable merits in terms of cost-effectiveness,easy manufacturing,and large scale applications.Nevertheless,the absence of a hole transport layer contributes ... Printable mesoscopic perovskite solar cells(PM-PSCs)possess notable merits in terms of cost-effectiveness,easy manufacturing,and large scale applications.Nevertheless,the absence of a hole transport layer contributes to the exacerbation of carrier recombination,and the defects between the perovskite and electron transport layer(ETL)interfaces significantly decrease the efficiency of the devices.In this study,a bifunctional surface passivation approach is proposed by applying a thioacetamide(TAA)surfactant on the mesoporous TiO_(2)interface.The results demonstrate that TAA molecules could interact with TiO_(2),thereby diminishing the oxygen vacancy defects.Additionally,the amino group and sulfur atoms in TAA molecules act as Lewis base to effectively passivate the uncoordinated Pb^(2+)in perovskite and improve the morphology of perovskite,and decrease the trap-state density of perovskite.The TAA passivation mechanism improves the alignment of energy levels between TiO_(2)and perovskite,facilitating electron transport and reducing carrier recombination.Consequently,the TAA-passivated device achieved a champion power conversion efficiency(PCE)of 17.86%with a high fill factor(FF)of 79.16%and an open-circuit voltage(V_(OC))of 0.971 V.This investigation presents a feasible strategy for interfacial passivation of the ETL to further improve the efficiency of PM-PSCs. 展开更多
关键词 Perovskite solarcells Carbon electrode THIOACETAMIDE Interfacial passivation
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椎间孔镜BEIS技术联合甲钴胺治疗腰椎间盘突出症患者的临床效果
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作者 刘二涛 秦晓东 +2 位作者 郭张建 丁正美 朱小建 《大医生》 2024年第21期9-12,共4页
目的探究椎间孔镜BEIS技术联合甲钴胺对腰椎间盘突出症患者的效果,为临床治疗提供参考。方法选取2021年2月至2023年2月南通市第四人民医院收治的100例腰椎间盘突出症患者为研究对象,按照随机数字表法分为对照组和观察组,各50例。对照组... 目的探究椎间孔镜BEIS技术联合甲钴胺对腰椎间盘突出症患者的效果,为临床治疗提供参考。方法选取2021年2月至2023年2月南通市第四人民医院收治的100例腰椎间盘突出症患者为研究对象,按照随机数字表法分为对照组和观察组,各50例。对照组患者接受椎板开窗术治疗,观察组患者接受椎间孔镜BEIS技术联合甲钴胺治疗。比较两组患者视觉模拟量表(VAS)疼痛评分、日本骨科协会(JOA)评分、Oswestry功能障碍指数问卷表(ODI)评分、炎症因子[C反应蛋白(CRP)、红细胞沉降率(ESR)]水平、相关恢复指标。结果两组患者VAS疼痛评分具有时间、组间、交互效应差异(F_(时间)=23.469,P时间<0.05;F_(组间)=19.861,P_(组间)<0.05;F_(交互)=10.256,P_(交互)<0.05)。两组患者术前及术后24 h、7 d、1个月、3个月的VAS疼痛评分均呈下降趋势,且观察组术后24 h~3个月的VAS疼痛评分均低于对照组(均P<0.05)。术后3个月,两组患者JOA评分均升高,且观察组高于对照组;两者患者ODI评分均降低,且观察组低于对照组(均P<0.05)。两组患者炎症因子水平均具有时间、组间、交互效应差异(CRP:F_(时间)=21.143,P时间<0.05;F_(组间)=18.251,P_(组间)<0.05;F_(交互)=24.452,P_(交互)<0.05。ESR:F_(时间)=21.127,P时间<0.05;F_(组间)=17.341,P_(组间)<0.05;F_(交互)=11.243,P_(交互)<0.05)。两组患者术前及术后7 d、3个月CRP水平及ESR均呈下降趋势,且观察组术后7 d~3个月均低于对照组(均P<0.05)。观察组患者独立行走时间、日常活动恢复时间、社会活动恢复时间均短于对照组(均P<0.05)。结论椎间孔镜BEIS技术联合甲钴胺对腰椎间盘突出症患者的临床效果较好,可改善缓解患者疼痛,促进腰椎功能的恢复,抑制炎症反应,缩短恢复时间,值得临床应用。 展开更多
关键词 椎间孔镜beiS技术 甲钴胺 腰椎间盘突出症
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Constructing Al@C-Sn pellet anode without passivation layer for lithium-ion battery
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作者 Kangzhe Cao Sitian Wang +3 位作者 Yanan He Jiahui Ma Ziwei Yue Huiqiao Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期552-561,共10页
Al is considered as a promising lithium-ion battery(LIBs)anode materials owing to its high theoretical capacity and appropri-ate lithation/de-lithation potential.Unfortunately,its inevitable volume expansion causes th... Al is considered as a promising lithium-ion battery(LIBs)anode materials owing to its high theoretical capacity and appropri-ate lithation/de-lithation potential.Unfortunately,its inevitable volume expansion causes the electrode structure instability,leading to poor cyclic stability.What’s worse,the natural Al2O3 layer on commercial Al pellets is always existed as a robust insulating barrier for elec-trons,which brings the voltage dip and results in low reversible capacity.Herein,this work synthesized core-shell Al@C-Sn pellets for LIBs by a plus-minus strategy.In this proposal,the natural Al2O3 passivation layer is eliminated when annealing the pre-introduced SnCl2,meanwhile,polydopamine-derived carbon is introduced as dual functional shell to liberate the fresh Al core from re-oxidization and alle-viate the volume swellings.Benefiting from the addition of C-Sn shell and the elimination of the Al2O3 passivation layer,the as-prepared Al@C-Sn pellet electrode exhibits little voltage dip and delivers a reversible capacity of 1018.7 mAh·g^(-1) at 0.1 A·g^(-1) and 295.0 mAh·g^(-1) at 2.0 A·g^(-1)(after 1000 cycles),respectively.Moreover,its diffusion-controlled capacity is muchly improved compared to those of its counterparts,confirming the well-designed nanostructure contributes to the rapid Li-ion diffusion and further enhances the lithium storage activity. 展开更多
关键词 lithium-ion battery high-performance anode aluminum passivation layer plus-minus strategy
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Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking
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作者 Luís Quinto Pedro Pinheiro +3 位作者 Sergio B.Goncalves Ivo Roupa Paula Simoes Miguel Tavares da Silva 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期62-68,共7页
Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational readiness.Several exoskeletons have been developed recently to address these chal... Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational readiness.Several exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday usability.This article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target population.Based on the 6-min walk test,twenty-nine subjects participated in the study using three different force elements.The results indicate that it is possible to reduce metabolic expenditure while using the developed exoskeleton.Additionally,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended periods.Nevertheless,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance. 展开更多
关键词 Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton GAIT BIOMECHANICS
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Limit state analysis of rigid retaining structures against seismically induced passive failure in heterogeneous soils
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作者 Jianfeng Zhou Changbing Qin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期1095-1105,共11页
Soils are not necessarily uniform and may present linearly varied or layered characteristics,for example the backfilled soils behind rigid retaining walls.In the presence of large lateral thrust imposed by arch bridge... Soils are not necessarily uniform and may present linearly varied or layered characteristics,for example the backfilled soils behind rigid retaining walls.In the presence of large lateral thrust imposed by arch bridge,passive soil failure is possible.A reliable prediction of passive earth pressure for the design of such wall is challenging in complicated soil strata,when adopting the conventional limit analysis method.In order to overcome the challenge for generating a kinematically admissible velocity field and a statically allowable stress field,finite element method is incorporated into limit analysis,forming finiteelement upper-bound(FEUB)and finite-element lower-bound(FELB)methods.Pseudo-static,original and modified pseudo-dynamic approaches are adopted to represent seismic acceleration inputs.After generating feasible velocity and stress fields within discretized elements based on specific criteria,FEUB and FELB formulations of seismic passive earth pressure(coefficient K_(P))can be derived from work rate balance equation and stress equilibrium.Resorting to an interior point algorithm,optimal upper and lower bound solutions are obtained.The proposed FEUB and FELB procedures are well validated by limit equilibrium as well as lower-bound and kinematic analyses.Parametric studies are carried out to investigate the effects of influential factors on seismic K_(P).Notably,true solution of K_(P) is well estimated based on less than 5%difference between FEUB and FELB solutions under such complex scenarios. 展开更多
关键词 Retaining wall passive earth pressure EARTHQUAKES Finite-element limit-analysis methods
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Synergistic defect passivation and strain compensation toward efficient and stable perovskite solar cells
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作者 Liqiang Bian Zhe Xin +12 位作者 Yuanyuan Zhao Lei Gao Zhi Dou Linde Li Qiyao Guo Jialong Duan Jie Dou Yingli Wang Xinyu Zhang Chi Jiang Liqing Sun Qiang Zhang Qunwei Tang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期327-333,共7页
Rational interface engineering is essential for minimizing interfacial nonradiative recombination losses and enhancing device performance.Herein,we report the use of bidentate diphenoxybenzene(DPOB)isomers as surface ... Rational interface engineering is essential for minimizing interfacial nonradiative recombination losses and enhancing device performance.Herein,we report the use of bidentate diphenoxybenzene(DPOB)isomers as surface modifiers for perovskite films.The DPOB molecules,which contain two oxygen(O)atoms,chemically bond with undercoordinated Pb^(2+) on the surface of perovskite films,resulting in compression of the perovskite lattice.This chemical interaction,along with physical regulations,leads to the formation of high-quality perovskite films with compressive strain and fewer defects.This compressive strain-induced band bending promotes hole extraction and transport,while inhibiting charge recombination at the interfaces.Furthermore,the addition of DPOB will reduce the zero-dimensional(OD) Cs_4PbBr_6 phase and produce the two-dimensional(2D) CsPb_(2)Br_5 phase,which is also conducive to the improvement of device performance.Ultimately,the resulting perovskite films,which are strain-released and defect-passivated,exhibit exceptional device efficiency,reaching 10.87% for carbon-based CsPbBr_(3) device,14.86% for carbon-based CsPbI_(2)Br device,22,02% for FA_(0.97)Cs_(0.03)PbI_(3) device,respectively.Moreover,the unencapsulated CsPbBr_(3) PSC exhibits excellent stability under persistent exposure to humidity(80%) and heat(80℃) for over 50 days. 展开更多
关键词 Perovskite solar cells Nonradiative recombination Chemical interaction Defect passivation Strain engineering
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A nano-sheet graphene-based enhanced thermal radiation composite for passive heat dissipation from vehicle batteries
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作者 Ji-Xiang Wang Christopher Salmean +5 位作者 Jiaxin Li Chaojie Lei Jun Li Mingliang Zhong Bo Qi Yufeng Mao 《Nano Materials Science》 EI CAS CSCD 2024年第4期443-455,共13页
In response to thermal runaway(TR)of electric vehicles,recent attention has been focused on mitigation strategies such as efficient heat dredging in battery thermal management.Thermal management with particular focus ... In response to thermal runaway(TR)of electric vehicles,recent attention has been focused on mitigation strategies such as efficient heat dredging in battery thermal management.Thermal management with particular focus on battery cooling has been becoming increasingly significant.TR usually happened when an electric vehicle is unpowered and charged.In this state,traditional active battery cooling schemes are disabled,which can easily lead to dangerous incidents due to loss of cooling ability,and advanced passive cooling strategies are therefore gaining importance.Herein,we developed an enhanced thermal radiation material,consisting of~1μm thick multilayered nano-sheet graphene film coated upon the heat dissipation surface,thereby enhancing thermal radiation in the nanoscale.The surface was characterized on the nanoscale,and tested in a battery-cooling scenario.We found that the graphene-based coating's spectral emissivity is between 91% and 95% in the mid-infrared region,and thermal experiments consequently illustrated that graphene-based radiative cooling yielded up to15.1% temperature reduction when compared to the uncoated analogue.Using the novel graphene surface to augment a heat pipe,the temperature reduction can be further enlarged to 25.6%.The new material may contribute to transportation safety,global warming mitigation and carbon neutralization. 展开更多
关键词 Battery thermal management Nano-sheet graphene Functional material passive cooling Thermal radiation
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LFM Radar Source Passive Localization Algorithm Based on Range Migration
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作者 Dandan Li Deyi Wang Hao Huan 《Journal of Beijing Institute of Technology》 EI CAS 2024年第2期130-140,共11页
Traditional single-satellite passive localization algorithms are influenced by frequency and angle measurement accuracies,resulting in error estimation of emitter position on the order of kilometers.Subsequently,a sin... Traditional single-satellite passive localization algorithms are influenced by frequency and angle measurement accuracies,resulting in error estimation of emitter position on the order of kilometers.Subsequently,a single-satellite localization algorithm based on passive synthetic aper-ture(PSA)was introduced,enabling high-precision positioning.However,its estimation of azimuth and range distance is considerably affected by the residual frequency offset(RFO)of uncoopera-tive system transceivers.Furthermore,it requires data containing a satellite flying over the radia-tion source for RFO search.After estimating the RFO,an accurate estimation of azimuth and range distance can be carried out,which is difficult to achieve in practical situations.An LFM radar source passive localization algorithm based on range migration is proposed to address the dif-ficulty in estimating frequency offset.The algorithm first provides a rough estimate of the pulse repetition time(PRT).It processes intercepted signals through range compression,range interpola-tion,and polynomial fitting to obtain range migration observations.Subsequently,it uses the changing information of range migration and an accurate PRT to formulate a system of nonlinear equations,obtaining the emitter position and a more accurate PRT through a two-step localization algorithm.Frequency offset only induces a fixed offset in range migration,which does not affect the changing information.This algorithm can also achieve high-precision localization in squint scenar-ios.Finally,the effectiveness of this algorithm is verified through simulations. 展开更多
关键词 passive localization range migration residual frequency offset
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Digital cancellation of multi-band passive inter-modulation based on Wiener-Hammerstein model
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作者 Jinxiang Liu Xiaotao Zhang +1 位作者 Jun Yang Huiping Yang 《Digital Communications and Networks》 SCIE CSCD 2024年第4期1189-1197,共9页
Utilizing multi-band and multi-carrier techniques enhances throughput and capacity in Long-Term Evolution(LTE)-Advanced and 5G New Radio(NR)mobile networks.However,these techniques introduce Passive Inter-Modulation(P... Utilizing multi-band and multi-carrier techniques enhances throughput and capacity in Long-Term Evolution(LTE)-Advanced and 5G New Radio(NR)mobile networks.However,these techniques introduce Passive Inter-Modulation(PIM)interference in Frequency-Division Duplexing(FDD)systems.In this paper,a novel multi-band Wiener-Hammerstein model is presented to digitally reconstruct PIM interference signals,thereby achieving effective PIM Cancellation(PIMC)in multi-band scenarios.In the model,transmitted signals are independently processed to simulate Inter-Modulation Distortions(IMDs)and Cross-Modulation Distortions(CMDs).Furthermore,the Finite Impulse Response(FIR)filter,basis function generation,and B-spline function are applied for precise PIM product estimation and generation in multi-band scenarios.Simulations involving 4 carrier components from diverse NR frequency bands at varying transmitting powers validate the feasibility of the model for multi-band PIMC,achieving up to 19 dB in PIMC performance.Compared to other models,this approach offers superior PIMC performance,exceeding them by more than 5 dB in high transmitting power scenarios.Additionally,its lower sampling rate requirement reduces the hardware complexity associated with implementing multi-band PIMC. 展开更多
关键词 passive inter-modulation Frequency-division duplexing Nonlinear distortion Digital cancellation Spline interpolation Wiener-Hammerstein model
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Zn Dissolution-Passivation Behavior with ZnO Formation via In Situ Characterizations
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作者 Tanyanyu Wang Masahiro Kunimoto +3 位作者 Masahiro Yanagisawa Masayuki Morita Takeshi Abe Takayuki Homma 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期193-200,共8页
In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical characterization.The Zn passivation during galvanostatic anodization merely follows the dis... In this study,ZnO formation during the dissolution-passivation process of Zn anodes is observed via in situ Raman and optical characterization.The Zn passivation during galvanostatic anodization merely follows the dissolution-precipitation model,whereas that of potentiodynamic polarization exhibits different behaviors in different potential ranges.Initially,the Zn electrode is gradually covered by a ZnO precipitation film and then undergoes solid-state oxidation at~255 mV.The starting point of solid-state oxidation is well indicated by the abrupt current drop and yellow coloration of the electrode surface.During the pseudo passivation,an intense current oscillation is observed.Further,blink-like color changes between yellow and dark blue are revealed for the first time,implying that the oscillation is caused by the dynamic adsorption and desorption of OH groups.The as-formed ZnOs then experience a dissolution-reformation evolution,during which the crystallinity of the primary ZnO film is improved but the solid-state-formed ZnO layer becomes rich in oxygen vacancies.Eventually,oxide densification is realized,contributing to the Zn passivation.This study provides new insights into the Zn dissolution-passivation behavior,which is critical for the future optimization of Zn batteries. 展开更多
关键词 in situ characterization Zn dissolution and passivation ZnO formation
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Role of self-assembled molecules’anchoring groups for surface defect passivation and dipole modulation in inverted perovskite solar cells
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作者 Xiaoyu Wang Muhammad Faizan +3 位作者 Kun Zhou Xinjiang Wang Yuhao Fu Lijun Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期108-115,共8页
Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication,low hysteresis effects,and high stability.Despite these advantages,their efficiency is currently limited b... Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication,low hysteresis effects,and high stability.Despite these advantages,their efficiency is currently limited by excessive defects and poor carrier transport at the perovskite-electrode interface,particularly at the buried interface between the perovskite and transparent conductive oxide(TCO).Recent efforts in the perovskite community have focused on designing novel self-assembled molecules(SAMs)to improve the quality of the buried interface.However,a notable gap remains in understanding the regulation of atomic-scale interfacial properties of SAMs between the perovskite and TCO interfaces.This understanding is crucial,particularly in terms of identifying chemically active anchoring groups.In this study,we used the star SAM([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)as the base structure to investigate the defect passivation effects of eight common anchoring groups at the perovskite-TCO interface.Our findings indicate that the phosphonic and boric acid groups exhibit notable advantages.These groups fulfill three key criteria:they provide the greatest potential for defect passivation,exhibit stable adsorption with defects,and exert significant regulatory effects on interface dipoles.Ionized anchoring groups exhibit enhanced passivation capabilities for defect energy levels due to their superior Lewis base properties,which effectively neutralize local charges near defects.Among various defect types,iodine vacancies are the easiest to passivate,whereas iodine-substituted lead defects are the most challenging to passivate.Our study provides comprehensive theoretical insights and inspiration for the design of anchoring groups in SAMs,contributing to the ongoing development of more efficient inverted perovskite solar cells. 展开更多
关键词 inverted perovskite solar cell defect passivation self-assembled molecule interface engineering first-principles calculation
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Improved efficiency and stability of inverse perovskite solar cells via passivation cleaning
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作者 Kunyang Ge Chunjun Liang 《Journal of Semiconductors》 EI CAS CSCD 2024年第10期74-83,共10页
Amidst the global energy and environmental crisis,the quest for efficient solar energy utilization intensifies.Perovskite solar cells,with efficiencies over 26%and cost-effective production,are at the forefront of res... Amidst the global energy and environmental crisis,the quest for efficient solar energy utilization intensifies.Perovskite solar cells,with efficiencies over 26%and cost-effective production,are at the forefront of research.Yet,their stability remains a barrier to industrial application.This study introduces innovative strategies to enhance the stability of inverted perovskite solar cells.By bulk and surface passivation,defect density is reduced,followed by a"passivation cleaning"using Apacl amino acid salt and isopropyl alcohol to refine film surface quality.Employing X-ray diffraction(XRD),scanning electron microscope(SEM),and atomic force microscopy(AFM),we confirmed that this process effectively neutralizes surface defects and curbs non-radiative recombination,achieving 22.6%efficiency for perovskite solar cells with the composition Cs_(0.15)FA_(0.85)PbI_(3).Crucially,the stability of treated cells in long-term tests has been markedly enhanced,laying groundwork for industrial viability. 展开更多
关键词 perovskite solar cells STABILITY surface passivation washing process photoelectric conversion efficiency nonradiative recombination
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