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Science China(Technological Sciences) 2024年第1期67卷 121-129页

作者： WANG YaSen YUAN ye fang HuaZhen DING Han School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering University of KansasLawrence 66045USA

In modern science and engineering disciplines,data-driven discovery methods play a fundamental role in system modeling,as data serve as the external representations of the intrinsic mechanisms within ***,empirical data contaminated by process and measurement noise remain a significant obstacle for this type of *** this study,we have developed a data-driven method capable of directly uncovering linear dynamical systems from noisy *** method combines the Kalman smoothing and sparse Bayesian learning to decouple process and measurement noise under the expectation-maximization framework,presenting an analytical method for alternate state estimation and system ***,the discovered model explicitly characterizes the probability distribution of process and measurement noise,as they are essential for filtering,smoothing,and stochastic *** have successfully applied the proposed algorithm to several simulation *** results demonstrate its potential to enable linear dynamical system discovery in practical applications where noise-free data are intractable to capture.

关键词： system identification sparse Bayesian learning Kalman smoothing process and measurement noise

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Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

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Journal of Iron and Steel Research International 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie Guo Xin-fang Zhang Yi-wa Luo ye Sun Jing Guo Rong-guang Yang Xiao-dan zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang Gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials *** effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these *** this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is *** parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

Deep Video Harmonization by Improving Spatial-temporal Consistency

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Machine Intelligence Research 2024年第1期21卷 46-54页

作者： Xiuwen Chen Li fang Long ye Qin Zhang Key Laboratory of Media Audio and Video Ministry of Education Communication University of ChinaBeijing 100024China

Video harmonization is an important step in video editing to achieve visual consistency by adjusting foreground appear-ances in both spatial and temporal *** methods always only harmonize on a single scale or ignore the inaccuracy of flow estimation,which leads to limited harmonization *** this work,we propose a novel architecture for video harmoniza-tion by making full use of spatiotemporal features and yield temporally consistent harmonized *** introduce multiscale harmon-ization by using nonlocal similarity on each scale to make the foreground more consistent with the *** also propose a fore-ground temporal aggregator to dynamically aggregate neighboring frames at the feature level to alleviate the effect of inaccurate estim-ated flow and ensure temporal *** experimental results demonstrate the superiority of our method over other state-of-the-art methods in both quantitative and visual comparisons.

关键词： Harmonization temporal consistency video editing video composition nonlocal similarity

Electrospun nanofibrous membranes with antimicrobial activity for air filtration

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Chinese Chemical Letters 2024年第10期35卷 173-183页

作者： Guangyao Wang Zhitong Xu ye Qi Yueguang fang Guiling Ning Junwei ye State Key Laboratory of Fine Chemicals and School of Chemical Engineering Dalian University of Technology Engineering Laboratory of Boric and Magnesic Functional Material Preparative and Applied Technology

Air pollution, including airborne pathogens and particulate matter(PM), has become a prominent issue affecting human health and safety. Conventional air filtration materials do not meet the requirements for efficient PM capture or do not instantly kill pathogens, leading to increased risk of direct/indirect contact transmission and infection due to the accumulation of pathogens during filtration. Electrospun nanofibrous membranes have emerged as a promising platform due to their rich porous structure, finer fiber diameters, good internal connectivity, and the ability to easily incorporate active chemicals for antimicrobial function. In this review, antimicrobial mechanisms of nanofibrous membranes for air filtration and PM capture mechanisms of nanofibers were firstly investigated, and various types of electrospun nanofibrous membranes with different antimicrobial agents for efficient air filtration were described in detail,including organic antimicrobial agents, inorganic antimicrobial agents and metal-organic frameworks. We hope this work could provide a better practical insight for designing novel electrospun nanofibrous membranes with antimicrobial efficacy for efficient air filtration.

关键词： Air filtration Antimicrobial Electrospinning Nanofibrous membrane Particulate matter

Sorely reducing emissions of non-methane short-lived climate forcers will worsen compound flood-heatwave extremes in the Northern Hemisphere

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Advances in Climate Change Research 2024年第4期15卷 737-750页

作者： Ying-fang LI Zhi-Li WANG Ya-Dong LEI Xiao-Chao YU Lin LIU Hui-zheng CHE Xiao-ye ZHANG State Key Laboratory of Severe Weather and Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China University of Chinese Academy of Sciences Beijing 100190China

Non-methane short-lived climate forcer(SLCF)or near-term climate forcer(NTCF)emissions,as a significant driver of climate change,can be reduced to improve air *** reductions may contribute to additional warming of the climate system in the short term,thereby strongly affecting the likelihood of climate ***,there has been no quantitative assessment of the impact of non-methane SLCF mitigation on compound flood-heatwave extremes(CFHEs).This study quantitatively investigates the changes in future(2031-2050 versus 1995-2014)CFHEs and the resulting population exposure in the Northern Hemisphere(NH)due to non-methane SLCF *** used multi-model ensemble simulations under two future scenarios from the Aerosol and Chemistry Model Intercomparison Project(AerChemMIP)in the Coupled Model Intercomparison Project Phase 6(CMIP6).The two future scenarios share the same greenhouse gas(GHG)emissions but have weak(Shared Socioeconomic Pathway(SSP)3-7.0)versus strong(SSP3-7.0-lowNTCF)levels of air quality control *** results show that future non-methane SLCF reductions during 2031-2050 results in about a 7.3%±2.3%increase in grid exposure to CFHEs in the NH relative to the period *** frequency,intensity,and duration of CFHEs increase by varying *** the period 2031-2050,the frequency of CFHEs across the NH increases by 2.9±0.9 events per decade due to non-methane SLCF *** increases in CFHE frequency are more pronounced in East Asia,South Asia,Siberia,and northern and eastern North *** East and South Asia,the in-tensities of both heatwaves and floods corresponding to CFHEs increase markedly,where heatwave magnitude(HWM)increases by 0.3±0.2 K in East Asia and weighted average precipitation(WAP)increases by 18.3%±15.3%and 12.0%±4.5%in East Asia and South Asia,*** other regions,rising temperatures dominate the increase in *** regard to the duration of CFHEs,future reductions in non-methane SLC

关键词： Non-methane SLCFs CHFEs Cleaner air Population exposure

Spatially explicit reconstruction of cropland cover in Europe from AD 1800 to 2000

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Science China Earth Sciences 2024年第9期67卷 2953-2971页

作者： Jun LI Yu ye Xiuqi fang Diyang ZHANG Zhilei WU Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China College of Geographical Science Qinghai Normal UniversityXining 810016China

One of the challenges in global change research is the significant uncertainty in global historical land use and land cover(LUCC)datasets,which are widely used as foundational *** addition to the regional cropland area reconstructions,improving the grid allocation method is another feasible way to raise the reliability of historical LUCC *** this study,an integrated reconstruction of the national cropland areas over the past 200 years was developed for 36 European *** that,the allocation algorithm was built using physiogeographic variables and historical city sites for accounting for land suitability and cultivation preferences,***,cropland data in Europe with a spatial resolution of 5′×5′at five time sections from AD 1800 to 2000 were generated using the optimal allocation algorithm in accordance with the stages of the regional *** results were as follows:(1)The dominant factors governing the distribution of croplands in Europe vary at different agricultural stages,but the results can be merged *** suitability was more optimal for allocation during the modern agricultural stage(AD 1950 and 2000);the priority index combined with land suitability and cultivation preference was more reasonable for allocation during the traditional agricultural stage(AD 1800).The average of the allocations by priority index and the land suitability could be adopted as the allocation results during the transitional stage(AD 1850 and 1900)because the grids for absolute differences within±10 and±20 percentage points between the results obtained from the above two allocations were above 80% and 95%,respectively,which means the two allocation results could be merged.(2)Over the past 200 years,the total cropland area in Europe first increased to a peak in AD 1900 and then ***,the centre of the higher cropland fraction shifted from the western part of Europe in AD 1800 to the eastern part of the continent after AD 1950.(3)

关键词： Land use and land cover change Historical cropland Gridding allocation Europe Past 200 years

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Preparation and properties of Ti_(3)SiC(2) -based corrosion mitigation coatings for SiC_(f) /SiC PWR accident tolerant fuel cladding

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Journal of Advanced Ceramics 2024年第1期13卷 73-85页

作者： Jinsong Yang fang ye Laifei Cheng Kai Zhao Yucong Wei Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China

To enhance the resistance of SiC_(f)/SiC to hydrothermal corrosion in the pressurized water reactor(PWR)environment,structurally tunable Ti_(3)SiC(2)-based corrosion mitigation coatings for SiC_(f)/SiC were prepared using molten salt *** influence of various process parameters,such as Si/Ti molar ratio in raw materials,annealing time,and annealing temperature,on the phase composition and the structure of the coatings was *** the process control,the fabricated coatings can be either Ti_(3)SiC(2) monolithic structure or TiC/Ti_(3)SiC(2) and TiC/Ti_(3)SiC(2)/Ti_(5)Si_(3)C_(x) multilayered *** coatings demonstrate strong bonding to the substrate due to in-situ reaction,exhibiting tensile and shear strength of at least 26.9 and 30.8 MPa,*** TiC as a transition layer further enhances the tensile and shear strength to 41.3 and 51.4 MPa,*** Ti_(3)SiC(2) coatings enhance the thermal conductivity of SiC_(f)/SiC by 10%–12%.Notably,Ti_(3)SiC(2) coatings effectively protect SiC_(f)/SiC from hydrothermal corrosion,demonstrating an 83%strength retention rate compared to 71%in the control group after ***,the Ti5Si3Cx layer exhibits unsatisfactory corrosion *** Ti_(3)SiC(2) monolithic coating has higher thermal conductivity,TiC/Ti_(3)SiC(2) multi-layered coating has higher bonding strength,and both have desirable resistance to the hydrothermal corrosion.

关键词： Ti_(3)SiC(2) SiC_(f)/SiC nuclear materials hydrothermal corrosion coating

Lithium Sulfur Batteries:Insights from Solvation Chemistry to Feasibility Designing Strategies for Practical Applications

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Energy & Environmental Materials 2024年第4期7卷 5-27页

作者： Jian Tan Longli Ma Yuan Wang Pengshu Yi Chuming ye Zhan fang Zhiheng Li Mingxin ye Jianfeng Shen Institute of Special Materials and Technology Fudan University Department of Materials Science Fudan University Department of Chemistry Fudan University

Rechargeable lithium-sulfur (Li-S) batteries,featuring high energy density,low cost,and environmental friendliness,have been dubbed as one of the most promising candidates to replace current commercial rechargeable Li-ion ***,their practical deployment has long been plagued by the infamous"shuttle effect"of soluble Li polysulfides (LiPSs) and the rampant growth of Li dendrites.

关键词： characterization tools design strategies Li–S batteries practical applications solvation chemistry

Dynamic Effect of Landslides Triggered by Earthquake:A Case Study in Moxi Town of Luding County,China

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Journal of Earth Science 2024年第1期35卷 221-234页

作者： Hongfu Zhou Fei ye Wenxi Fu Bin Liu Tian fang Rui Li Chengdu Center China Geological SurveyChengdu 610081China State Key Laboratory of Hydraulics and Mountain Rivers Protection Sichuan UniversityChengdu 610065China Sichuan Geological Survey Chengdu610081China Shandong University of Science and Technology Qingdao 266590China

The dynamic effect is a very important issue widely debated by scholars when studying the genetic and disaster-causing mechanisms of earthquake-triggered ***,the dynamic effect mechanism and phenomena of earthquake-triggered landslides were summarized in this ***,the primary types of dynamic effects were further used to interpret the Mogangling landslide in Moxi Town of Luding County,China.A field investigation,remote sensing,numerical calculation and theoretical analysis were carried out to illustrate the failure mechanism of slope rock masses affected by *** interaction between seismic waves and slope rock masses and the induced dynamic effect of slope rock masses were primarily accounted for in the *** slope topography,rock mass weathering and unloading characteristics,river erosion,regional seismogenic structure,and rock mass structure characteristics were also *** results showed that the formation of the Mogangling landslide was mainly related to the high amplification effect of seismic acceleration and back slope effects,interface dynamic stress effects,and double-sided slope effects of seismic waves caused by the catastrophic Ms 7.75 Moxi Earthquake in *** principles for the site and route selection of large-scale infrastructure in the planning stage and the scientific prevention of seismic geological disasters were proposed on the basis of the dynamic effect of earthquake-induced landslides.

关键词： dynamic effect coupling of endogenic and exogenic processes landslides earthquakes disaster prevention

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