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Tensile Properties of TWIP Steel at High Strain Rate

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Journal of Iron and Steel Research International 2009年第1期16卷 81-86,21页

作者： xiONG Rong-gang FU Ren-yu SU Yu li Qian WEI xi-cheng li lin School of Materials Science and Engineering Shanghai University Shanghai 200072 China

Tensile tests of TWIP steels of two compositions are performed in the strain rate range of 10^-5-10^3 s^-1. Results indicate that steel 1^# does not exhibit TWIP effect but deformation-induced martensitic transformation appears only. There exists TWIP effect in steel 3^# . Tensile properties at room temperature are sensitive to strain rate in the studied strain rate ranges. Analysis on the relationship between strain-hardening exponent and strain rates shows that strain induced martensitic transformation and formation of twins during deformation have significant in- fluence on their strain-hardening behavior.

关键词： twin-induced plasticity strain rate strain hardening deformation twin

Dynamics of bubble-shaped Bose-Einstein condensates on two-dimensional cross-section in micro-gravity environment

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Chinese Physics B 2023年第9期32卷 200-205页

作者：张铁夫李成蹊刘伍明 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

We investigated the dynamic evolution and interference phenomena of bubble-shaped Bose-Einstein condensates achievable in a micro-gravity *** numerical solutions of the Gross-Pitaevskii equation describing the dynamic evolution of the bubble-shaped Bose-Einstein condensates,we plotted the evolution of the wave function density distribution on its two-dimensional(2D)cross-section and analysed the resulting *** found that changes in the strength of atomic interactions and initial momentum can affect the dynamic evolution of the bubble-shaped Bose-Einstein condensates and their interference ***,we have observed that when the initial momentum is sufficiently high,the thickness of the bubble-shaped Bose-Einstein condensate undergoes a counterintuitive thinning,which is a counterintuitive result that requires further *** findings are poised to advance our comprehension of the physical essence of bubble-shaped Bose-Einstein condensates and to facilitate the development of relevant experiments in microgravity environments.

关键词： boson systems ultracold gases dynamic properties of condensates

Control of Corner Separation for a linear Compressor Cascade via Bionic Slanting Riblets at the Endwall

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Journal of Thermal Science 2025年第1期34卷 129-144页

作者： ZHANG Peng li Yonghong cheng Rixin Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation University of China College of Aeronautical Engineering Civil Aviation University of China

A new passive control approach,utilizing bionic slanting riblets,is employed to mitigate the flow close to the blade endwall in a linear cascade,and its effectiveness and mechanism in controlling corner separation are investigated through numerical *** slanting riblets are positioned at the endwall upstream of the cascade channel,and the influence of riblet height,yaw angle and relative position on the control of corner separation is *** findings indicate that the application of slanting riblets can efficiently counteract corner separation across the stable operational ***,the introduction of riblets with a height of merely 0.1 times the boundary layer thickness results in a significant reduction in total pressure loss by up to 14.53%,while simultaneously enhancing the static pressure coefficient by 21.74%.Flow analysis reveals that minute vortices produced within the riblet channels tend to coalesce,forming a potent large-scale vortex near the boundary layer's base *** phenomenon results in reduced additional losses compared to conventional vortex ***,the induced vortex promotes enhanced mixing between the mainstream flow and boundary layer,inhibiting the lateral displacement of low-energy fluids within the endwall boundary ***,this delays the onset of separation vortex formation and eliminates vortex rings in the corner region,ultimately enhancing the aerodynamic efficiency of the cascade.

关键词： additional losses compressor cascade corner separation slanting riblets vortex generator

Temporal variations of reference evapotranspiration and controlling factors:Implications for climatic drought in karst areas

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Journal of Groundwater Science and Engineering 2022年第3期10卷 267-284页

作者： xiao-jiao Guo Wen-zhong Wang cheng-xi li Wei Wang Jian-sheng Shi Ying Miao xing-bo Hao Dao-xian Yuan Key Laboratory of Groundwater Sciences and Engineering Ministry of Natural ResourcesInstitute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesShijiazhuang 050061China Ecogeological Survey Center of China Geological Survey China Aero Geophysical Survey and Remote Sensing Center for Natural ResourcesBeijing 100083China China University of Geosciences(Wuhan) Wuhan 430074China Key Laboratory of Karst Dynamics Institute of Karst GeologyChinese Academy of Geological SciencesGuilin 541004GuangxiChina Geological Exploration Institute of Shandong Zhengyuan China Metallurgical Geology BureauJinan 250101China Hebei Coal Geology Bureau fourth Geological Brigade Zhangjiakou 075100HebeiChina.

Variations in reference evapotranspiration(ET_(0)) and drought characteristics play a key role in the effect of climate change on water cycle and associated ecohydrological *** accurate estimation of ET_(0) is still a challenge due to the lack of meteorological data and the heterogeneity of hydrological *** there is an increasing trend in extreme drought events with global climate change,the relationship between ET_(0) and aridity index in karst areas has been poorly *** this study,we used the Penman-Monteith method based on a long time series of meteorological data from 1951 to 2015 to calculate ET_(0)in a typical karst area,Guilin,Southwest *** temporal variations in climate variables,ET_(0)and aridity index(AI)were analyzed with the Mann-Kendall trend test and linear regression to determine the climatic characteristics,associated controlling factors of ET_(0) variations,and further to estimate the relationship between ET_(0) and *** found that the mean,maximum and minimum temperatures had increased significantly during the 65-year study period,while sunshine duration,wind speed and relative humidity exhibited significant decreasing *** annual ET_(0) showed a significant decreasing trend at the rate of−8.02 mm/***,significant increase in air temperature should have contributed to the enhancement of ET_(0),indicating an“evaporation paradox”.In comparison,AI showed a slightly declining trend of−0.0005/a during *** change in sunshine duration was the major factor causing the decrease in ET_(0),followed by wind *** had a higher correlation with precipitation amount,indicating that the variations of AI was more dependent on precipitation,but not substantially dependent on the ET_(0).Although AI was not directly related to ET_(0),ET_(0)had a major contribution to seasonal AI *** seasonal variations of ET_(0)played a critical role in dryness/wetness changes to regulate water and energy supply,which

关键词： Reference evapotranspiration Aridity index Penman-Monteith method Sunshine duration Guilin

Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： li-Xu You Lan Tian Chun-ling Guo Shun-xi li Yu-cheng liu Yu-Long li Wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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A Hybrid Approach for Pavement Crack Detection Using Mask R-CNN and Vision Transformer Model

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Computers, Materials & Continua 2025年第1期82卷 561-577页

作者： Shorouq Alshawabkeh li Wu Daojun Dong Yao cheng liping li Faculty of Engineering China University of GeosciencesWuhan430074China

Detecting pavement cracks is critical for road safety and infrastructure *** methods,relying on manual inspection and basic image processing,are time-consuming and prone to *** deep-learning(DL)methods automate crack detection,but many still struggle with variable crack patterns and environmental *** study aims to address these limitations by introducing the Masker Transformer,a novel hybrid deep learning model that integrates the precise localization capabilities of Mask Region-based Convolutional Neural Network(Mask R-CNN)with the global contextual awareness of Vision Transformer(ViT).The research focuses on leveraging the strengths of both architectures to enhance segmentation accuracy and adaptability across different pavement *** evaluated the performance of theMaskerTransformer against other state-of-theartmodels such asU-Net,TransformerU-Net(TransUNet),U-NetTransformer(UNETr),SwinU-NetTransformer(Swin-UNETr),You Only Look Once version 8(YoloV8),and Mask R-CNN using two benchmark datasets:Crack500 and *** findings reveal that the MaskerTransformer significantly outperforms the existing models,achieving the highest Dice SimilarityCoefficient(DSC),precision,recall,and F1-Score across both ***,the model attained a DSC of 80.04%on Crack500 and 91.37%on DeepCrack,demonstrating superior segmentation accuracy and *** high precision and recall rates further substantiate its effectiveness in real-world applications,suggesting that the Masker Transformer can serve as a robust tool for automated pavement crack detection,potentially replacing more traditional methods.

关键词： Pavement crack segmentation transportation deep learning vision transformer Mask R-CNN image segmentation

Tailoring light–Matter Interactions in Overcoupled Resonator for Biomolecule Recognition and Detection

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Nano-Micro Letters 2025年第1期17卷 262-280页

作者： Dongxiao li Hong Zhou Zhihao Ren cheng Xu chengkuo Lee Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Center for Intelligent Sensors and MEMS(CISM) National University of SingaporeSingapore 117608Singapore

Plasmonic nanoantennas provide unique opportunities for precise control of light–matter coupling in surface-enhanced infrared absorption(SEIRA)spectroscopy,but most of the resonant systems realized so far suffer from the obstacles of low sensitivity,narrow bandwidth,and asymmetric Fano resonance ***,we demonstrated an overcoupled resonator with a high plasmon-molecule coupling coefficient(μ)(OC-Hμresonator)by precisely controlling the radiation loss channel,the resonator-oscillator coupling channel,and the frequency detuning *** observed a strong dependence of the sensing performance on the coupling state,and demonstrated that OC-Hμresonator has excellent sensing properties of ultra-sensitive(7.25%nm^(−1)),ultra-broadband(3–10μm),and immune asymmetric Fano *** characteristics represent a breakthrough in SEIRA technology and lay the foundation for specific recognition of biomolecules,trace detection,and protein secondary structure analysis using a single array(array size is 100×100μm^(2)).In addition,with the assistance of machine learning,mixture classification,concentration prediction and spectral reconstruction were achieved with the highest accuracy of 100%.Finally,we demonstrated the potential of OC-Hμresonator for SARS-CoV-2 *** findings will promote the wider application of SEIRA technology,while providing new ideas for other enhanced spectroscopy technologies,quantum photonics and studying light–matter interactions.

关键词： Plasmonic nanoantennas light-matter interaction Surface-enhanced infrared absorption Overcoupled Biosensing

FUBP3 mediates the amyloid-β-induced neuronal NLRP3 expression

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Neural Regeneration Research 2025年第7期20卷 2068-2083页

作者： Jing Yao Yuan li xi liu Wenping liang Yu li liyong Wu Zhe Wang Weihong Song The National Clinical Research Center for Geriatric Disease Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Pediatrics The Second Affiliated Hospital and Yuying Children’s HospitalKey Laboratory of Alzheimer’s Disease of Zhejiang ProvinceInstitute of AgingWenzhou Medical UniversityWenzhouZhejiang ProvinceChina Oujiang Laboratory(Zhejiang Laboratory for Regenerative Medicine Visionand Brain Health)WenzhouZhejiang ProvinceChina

Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the *** NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and *** NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory ***,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau *** biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in *** primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis *** the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical *** analysis suggested that FUBP3 plays a role in neuron-mediated immune *** also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced *** findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in *** that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.

关键词： 5′end trimming Alzheimer's disease amyloid-beta amyloid-β-dependent transcription FUBP3 inflammasome inflammation neuron NLRP3 tau transcription factor

A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy

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Computers, Materials & Continua 2025年第1期82卷 997-1026页

作者： li Ma Cai Dai xingsi Xue cheng Peng School of Computer Science Shaanxi Normal UniversityXi’an710119China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou350118China Information Construction and Management Center and Institute of Artificial Intelligence and Educational New Productivity Ningxia Normal UniversityGuyuan756099China

The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization *** the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search ***,two update strategies based on decomposition are used to update the evolving population and external archive,***,a multiselection strategy is *** first strategy is for the subspace without a non-dominated *** the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global *** second strategy is for the subspace with a non-dominated *** the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local *** third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated *** the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to ***,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search ***,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test *** results show that the proposed algorithm has better performance.

关键词： Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy