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The Effects of Infrastructure Projects on House Prices and Rents:Evidence from the HS2 Extension Cancellation in the UK
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作者 Wentao Zhu 《Journal of Sustainable Business and Economics》 2024年第2期76-94,共19页
This paper uses the HS2 extension cancellation in November 2021 as a quasi-experiment to study its impact on house prices and rents in Leeds.Using a DiD approach on repeat sales and monthly rents,I compare property va... This paper uses the HS2 extension cancellation in November 2021 as a quasi-experiment to study its impact on house prices and rents in Leeds.Using a DiD approach on repeat sales and monthly rents,I compare property values near the HS2 station and proposed construction site before and after the announcement.Results show a 3.6%decrease in house prices and a 3.9%decline in rents near the station,while properties near the construction site experienced a 2.4%increase in prices and a 2.1%rise in rents.This is the first paper to analyse the HS2 cancellation effect using panel data methods. 展开更多
关键词 HS2 extension cancellation Externalities House price effects Transport infrastructure Difference-in-Differences Model
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三色膏联合PRICE疗法治疗急性踝关节Ⅰ和Ⅱ度扭伤的临床效果
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作者 邱承玺 殷苏勤 +5 位作者 蔡晓辉 徐凯捷 牛锋 徐建德 詹红生 高慧 《中国当代医药》 CAS 2024年第27期85-88,共4页
目的探讨三色膏联合PRICE疗法治疗急性踝关节Ⅰ、Ⅱ度扭伤的临床效果。方法选取2022年2月至2023年5月上海市嘉定区中医医院骨伤科收治的52例Ⅰ、Ⅱ度急性踝关节扭伤患者作为研究对象,其中急诊患者35例,门诊患者17例,采用随机数字表法将... 目的探讨三色膏联合PRICE疗法治疗急性踝关节Ⅰ、Ⅱ度扭伤的临床效果。方法选取2022年2月至2023年5月上海市嘉定区中医医院骨伤科收治的52例Ⅰ、Ⅱ度急性踝关节扭伤患者作为研究对象,其中急诊患者35例,门诊患者17例,采用随机数字表法将其分为对照组和观察组,每组均失访1例,两组各25例纳入统计。对照组采用PRICE疗法治疗,观察组采用三色膏联合PRICE疗法,两组患者均治疗1周,治疗结束后,比较两组患者治疗前和治疗后第1、3周的视觉模拟评分法(VAS)评分及Mazur功能评分。结果52例患者中50例得到随访,随访时间不短于4周。治疗1、3周后,两组患者的VAS评分低于本组治疗前,Mazur功能评分高于本组治疗前,观察组的VAS评分低于对照组,Mazur功能评分高于对照组,差异有统计学意义(P<0.05)。结论三色膏联合PRICE疗法治疗急性踝关节Ⅰ、Ⅱ度扭伤可以获得更好的疗效,具有重要的临床价值和推广意义。 展开更多
关键词 三色膏 price疗法 踝关节 急性扭伤
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Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
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作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
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Seismic response of a mid-story isolated structure considering SSI in mountainous areas under long-period earthquakes 被引量:1
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作者 Wan Feng Qin Shengwu +7 位作者 Liu Dewen Zhao Tiange Zheng Yanping Shan Hang Li Zhiang Peng Fusong Xu Jingran Lei Min 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期151-161,共11页
At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is es... At present,there is not much research on mid-story isolated structures in mountainous areas.In this study,a model of a mid-story isolated structure considering soil-structure interaction(SSI)in mountainous areas is established along with a model that does not consider SSI.Eight long-period earthquake waves and two ordinary earthquake waves are selected as inputs for the dynamic time history analysis of the structure.The results show that the seismic response of a mid-story isolated structure considering SSI in mountainous areas can be amplified when compared with a structure that does not consider SSI.The structure response under long-period earthquakes is larger than that of ordinary earthquakes.The structure response under far-field harmonic-like earthquakes is larger than that of near-fault pulse-type earthquakes.The structure response under near-fault pulse-type earthquakes is larger than that of far-field non-harmonic earthquakes.When subjected to long-period earthquakes,the displacement of the isolated bearings exceeded the limit value,which led to instability and overturning of the structure.The structure with dampers in the isolated story could adequately control the nonlinear response of the structure,effectively reduce the displacement of the isolated bearings,and provide a convenient,efficient and economic method not only for new construction but also to retrofit existing structures. 展开更多
关键词 SSI in mountainous areas long-period earthquakes mid-story isolated structure structural dynamic analysis
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OptoGPT: A foundation model for inverse design in optical multilayer thin film structures 被引量:1
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作者 Taigao Ma Haozhu Wang L.Jay Guo 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第7期4-16,共13页
Optical multilayer thin film structures have been widely used in numerous photonic applications.However,existing inverse design methods have many drawbacks because they either fail to quickly adapt to different design... Optical multilayer thin film structures have been widely used in numerous photonic applications.However,existing inverse design methods have many drawbacks because they either fail to quickly adapt to different design targets,or are difficult to suit for different types of structures,e.g.,designing for different materials at each layer.These methods also cannot accommodate versatile design situations under different angles and polarizations.In addition,how to benefit practical fabrications and manufacturing has not been extensively considered yet.In this work,we introduce OptoGPT(Opto Generative Pretrained Transformer),a decoder-only transformer,to solve all these drawbacks and issues simultaneously. 展开更多
关键词 multilayer thin film structure inverse design foundation models deep learning structural color
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Understanding the Relationship Between Shrinking Cities and Land Prices:Spatial Pattern,Effectiveness,and Policy Implications 被引量:1
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作者 WANG Xiaohui PENG Li +1 位作者 HUANG Kexin DENG Wei 《Chinese Geographical Science》 SCIE CSCD 2024年第1期1-18,共18页
Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(ex... Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of analysis.By employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this influence.The findings demonstrate the following:1)there were 613 shrinking cities in China,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial regions.This study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas. 展开更多
关键词 shrinking cities land price propensity score matching(PSM) relative effectiveness China
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A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity 被引量:5
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作者 Qiaoyun Li Zuman Dou +5 位作者 Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期494-505,共12页
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic... In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods. 展开更多
关键词 Sea buckthorn Extraction method structure Rheological properties Antioxidant activity Bile acid binding capacity
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Mechanical responses of anchoring structure under triaxial cyclic loading 被引量:2
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作者 Peng Wang Nong Zhang +5 位作者 Qun Wei Xingliang Xu Guangzhen Cui Aoran Li Sen Yang Jiaguang Kan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期545-560,共16页
Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and failure.This study develops an experimental device designed to test AS under triaxial loads.The device enables the inves... Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and failure.This study develops an experimental device designed to test AS under triaxial loads.The device enables the investigation of the mechanical response,failure mode,instability assessment criteria,and anchorage effect of AS subjected to combined cyclic dynamic-static triaxial stress paths.The results show that the peak bearing strength is positively correlated with the anchoring matrix strength,anchorage length,and edgewise compressive strength.The bearing capacity decreases significantly when the anchorage direction is severely inclined.The free face failure modes are typically transverse cracking,concave fracturing,V-shaped slipping and detachment,and spallation detachment.Besides,when the anchoring matrix strength and the anchorage length decrease while the edgewise compressive strength,loading rate,and anchorage inclination angle increase,the failure intensity rises.Instability is determined by a negative tangent modulus of the displacement-strength curve or the continued deformation increase against the general downward trend.Under cyclic loads,the driving force that breaks the rock mass along the normal vector and the rigidity of the AS are the two factors that determine roadway stability.Finally,a control measure for surrounding rock stability is proposed to reduce the internal driving force via a pressure relief method and improve the rigidity of the AS by full-length anchorage and grouting modification. 展开更多
关键词 Triaxial stress Dynamic-static combination load Cyclic loading Anchoring structure(AS) Cumulative damage
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Seabed structures and foundations related to deep-sea resource development:A review based on design and research 被引量:1
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作者 Shengjie Rui Haojie Zhang +3 位作者 Hang Xu Xing Zha Mengtao Xu Kanmin Shen 《Deep Underground Science and Engineering》 2024年第2期131-148,共18页
The deep‐sea ground contains a huge amount of energy and mineral resources,for example,oil,gas,and minerals.Various infrastructures such as floating structures,seabed structures,and foundations have been developed to... The deep‐sea ground contains a huge amount of energy and mineral resources,for example,oil,gas,and minerals.Various infrastructures such as floating structures,seabed structures,and foundations have been developed to exploit these resources.The seabed structures and foundations can be mainly classified into three types:subsea production structures,offshore pipelines,and anchors.This study reviewed the development,installation,and operation of these infrastructures,including their structures,design,installation,marine environment loads,and applications.On this basis,the research gaps and further research directions were explored through this literature review.First,different floating structures were briefly analyzed and reviewed to introduce the design requirements of the seabed structures and foundations.Second,the subsea production structures,including subsea manifolds and their foundations,were reviewed and discussed.Third,the basic characteristics and design methods of deep‐sea pipelines,including subsea pipelines and risers,were analyzed and reviewed.Finally,the installation and bearing capacity of deep‐sea subsea anchors and seabed trench influence on the anchor were reviewed.Through the review,it was found that marine environment conditions are the key inputs for any offshore structure design.The fabrication,installation,and operation of infrastructures should carefully consider the marine loads and geological conditions.Different structures have their own mechanical problems.The fatigue and stability of pipelines mainly depend on the soil‐structure interaction.Anchor selection should consider soil types and possible trench formation.These focuses and research gaps can provide a helpful guide on further research,installation,and operation of deep‐sea structures and foundations. 展开更多
关键词 ANCHORS floating structures pipelines RISERS subsea foundations
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Web Layout Design of Large Cavity Structures Based on Topology Optimization 被引量:1
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作者 Xiaoqiao Yang Jialiang Sun Dongping Jin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2665-2689,共25页
Large cavity structures are widely employed in aerospace engineering, such as thin-walled cylinders, blades andwings. Enhancing performance of aerial vehicles while reducing manufacturing costs and fuel consumptionhas... Large cavity structures are widely employed in aerospace engineering, such as thin-walled cylinders, blades andwings. Enhancing performance of aerial vehicles while reducing manufacturing costs and fuel consumptionhas become a focal point for contemporary researchers. Therefore, this paper aims to investigate the topologyoptimization of large cavity structures as a means to enhance their performance, safety, and efficiency. By usingthe variable density method, lightweight design is achieved without compromising structural strength. Theoptimization model considers both concentrated and distributed loads, and utilizes techniques like sensitivityfiltering and projection to obtain a robust optimized configuration. The mechanical properties are checked bycomparing the stress distribution and displacement of the unoptimized and optimized structures under the sameload. The results confirm that the optimized structures exhibit improved mechanical properties, thus offering keyinsights for engineering lightweight, high-strength large cavity structures. 展开更多
关键词 Topology optimization lightweight design web layout design cavity structure
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Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation 被引量:2
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作者 Jingjing Liang Meina Zhang +6 位作者 Xiaohan Li Yuan Yue Xiaowei Wang Mengzhen Han Tianli Yue Zhouli Wang Zhenpeng Gao 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期421-433,共13页
Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were... Plant-based fermentations provide an untapped source for novel biotechnological applications.In this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus edodes.Polysaccharides were extracted from fermented and non-fermented L.edodes and purified via DEAE-52 and Sephadex G-100.The components designated F-LEP-2a and NF-LEP-2a were analyzed by FT-IR,HPGPC,HPAEC,SEM,GC-MS and NMR.The results revealed that probiotic fermentation increased the molecular weight from 1.16×10^(4) Da to 1.87×10^(4) Da and altered the proportions of glucose,galactose and mannose,in which glucose increased from 45.94%to 48.16%.Methylation analysis and NMR spectra indicated that F-LEP-2a and NF-LEP-2a had similar linkage patterns.Furthermore,their immunomodulatory activities were evaluated with immunosuppressive mice.NF-LEP and F-LEP improved immune organ indices,immunoglobulin(Ig G and Ig M)and cytokines concentrations;restored the antioxidation capacity of liver;and maintained the balance of gut microbiota.F-LEP displayed better moderating effects on the spleen index,immunoglobulin,cytokines and the diversity of gut microbiota than NF-LEP(200,400 mg/kg).Our study provides an efficient and environment-friendly way for the structural modification of polysaccharides,which helps to enhance their biological activity and promote their wide application in food,medicine and other fields. 展开更多
关键词 Lentinus edodes polysaccharide Lactobacillus fermentum fermentation Structural analysis Immunoregulatory activity Nuclear magnetic resonance
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Quantitatively characterizing sandy soil structure altered by MICP using multi-level thresholding segmentation algorithm 被引量:1
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作者 Jianjun Zi Tao Liu +3 位作者 Wei Zhang Xiaohua Pan Hu Ji Honghu Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4285-4299,共15页
The influences of biological,chemical,and flow processes on soil structure through microbially induced carbonate precipitation(MICP)are not yet fully understood.In this study,we use a multi-level thresholding segmenta... The influences of biological,chemical,and flow processes on soil structure through microbially induced carbonate precipitation(MICP)are not yet fully understood.In this study,we use a multi-level thresholding segmentation algorithm,genetic algorithm(GA)enhanced Kapur entropy(KE)(GAE-KE),to accomplish quantitative characterization of sandy soil structure altered by MICP cementation.A sandy soil sample was treated using MICP method and scanned by the synchrotron radiation(SR)micro-CT with a resolution of 6.5 mm.After validation,tri-level thresholding segmentation using GAE-KE successfully separated the precipitated calcium carbonate crystals from sand particles and pores.The spatial distributions of porosity,pore structure parameters,and flow characteristics were calculated for quantitative characterization.The results offer pore-scale insights into the MICP treatment effect,and the quantitative understanding confirms the feasibility of the GAE-KE multi-level thresholding segmentation algorithm. 展开更多
关键词 Soil structure MICRO-CT Multi-level thresholding MICP Genetic algorithm(GA)
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Tuning electronic structure of RuO_(2)by single atom Zn and oxygen vacancies to boost oxygen evolution reaction in acidic medium 被引量:1
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作者 Qing Qin Tiantian Wang +7 位作者 Zijian Li Guolin Zhang Haeseong Jang Liqiang Hou Yu Wang Min Gyu Kim Shangguo Liu Xien Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期94-102,I0003,共10页
The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct ... The poor stability of RuO_(2)electrocatalysts has been the primary obstacles for their practical application in polymer electrolyte membrane electrolyzers.To dramatically enhance the durability of RuO_(2)to construct activity-stability trade-off model is full of significance but challenging.Herein,a single atom Zn stabilized RuO_(2)with enriched oxygen vacancies(SA Zn-RuO_(2))is developed as a promising alternative to iridium oxide for acidic oxygen evolution reaction(OER).Compared with commercial RuO_(2),the enhanced Ru–O bond strength of SA Zn-RuO_(2)by forming Zn-O-Ru local structure motif is favorable to stabilize surface Ru,while the electrons transferred from Zn single atoms to adjacent Ru atoms protects the Ru active sites from overoxidation.Simultaneously,the optimized surrounding electronic structure of Ru sites in SA ZnRuO_(2)decreases the adsorption energies of OER intermediates to reduce the reaction barrier.As a result,the representative SA Zn-RuO_(2)exhibits a low overpotential of 210 mV to achieve 10 mA cm^(-2)and a greatly enhanced durability than commercial RuO_(2).This work provides a promising dual-engineering strategy by coupling single atom doping and vacancy for the tradeoff of high activity and catalytic stability toward acidic OER. 展开更多
关键词 ELECTROCATALYST Acidic oxygen evolution reaction Electronic structure engineering DURABILITY Reaction barrier
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From VIB‑to VB‑Group Transition Metal Disulfides:Structure Engineering Modulation for Superior Electromagnetic Wave Absorption 被引量:1
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作者 Junye Cheng Yongheng Jin +10 位作者 Jinghan Zhao Qi Jing Bailong Gu Jialiang Wei Shenghui Yi Mingming Li Wanli Nie Qinghua Qin Deqing Zhang Guangping Zheng Renchao Che 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期218-257,共40页
The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various field... The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance. 展开更多
关键词 Transition metal disulfides Electromagnetic wave absorption Impedance matching structure engineering modulation
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Multi-Material Topology Optimization for Spatial-Varying Porous Structures 被引量:1
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作者 Chengwan Zhang Kai Long +4 位作者 Zhuo Chen Xiaoyu Yang Feiyu Lu Jinhua Zhang Zunyi Duan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期369-390,共22页
This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volu... This paper aims to propose a topology optimization method on generating porous structures comprising multiple materials.The mathematical optimization formulation is established under the constraints of individual volume fraction of constituent phase or total mass,as well as the local volume fraction of all phases.The original optimization problem with numerous constraints is converted into a box-constrained optimization problem by incorporating all constraints to the augmented Lagrangian function,avoiding the parameter dependence in the conventional aggregation process.Furthermore,the local volume percentage can be precisely satisfied.The effects including the globalmass bound,the influence radius and local volume percentage on final designs are exploited through numerical examples.The numerical results also reveal that porous structures keep a balance between the bulk design and periodic design in terms of the resulting compliance.All results,including those for irregular structures andmultiple volume fraction constraints,demonstrate that the proposedmethod can provide an efficient solution for multiple material infill structures. 展开更多
关键词 Topology optimization porous structures local volume fraction augmented lagrangian multiple materials
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Generation of structured light beams with polarization variation along arbitrary spatial trajectories using tri-layer metasurfaces 被引量:2
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作者 Tong Nan Huan Zhao +3 位作者 Jinying Guo Xinke Wang Hao Tian Yan Zhang 《Opto-Electronic Science》 2024年第5期1-11,共11页
Conventionally,the spatially structured light beams produced by metasurfaces primarily highlight the polarization modulation of the beams propagating along the optical axis or the beams'spatial transmission trajec... Conventionally,the spatially structured light beams produced by metasurfaces primarily highlight the polarization modulation of the beams propagating along the optical axis or the beams'spatial transmission trajectory.In particular,along the optical axis,the polarization state is either constant or varies continuously in each output plane.Here,we develop innovative spatially structured light beams with continually changing polarization along any arbitrary spatial transmission trajectories.With tri-layer metallic metasurfaces,the geometric characteristics of each layer structure can be adjusted to modulate the phase and polarization state of the incident terahertz(THz)wave.The beam will converge to the predefined trajectory along several paths to generate a Bessel-like beam with longitudinal polarization changes.We demonstrate the versatility of the approach by designing two THz-band structured light beams with varying polarization states along the spatial helical transmission trajectory.Continuous linear polarization changes and linear polarization to right circular polarization(RCP)and back to linear polarization changes are realized respectively.The experimental results are basically consistent with the simulated results.Our proposal for arbitrary trajectory structured light beams with longitudinally varying polarization offers a practical method for continuously regulating the characteristics of spatial structured light beams with non-axial transmission.This technique has potential uses in optical encryption,particle manipulation,and biomedical imaging. 展开更多
关键词 structured light beam tri-layer metallic metasurface longitudinal polarization non-axial transmission
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Ultrafast dynamics of femtosecond laser-induced high spatial frequency periodic structures on silicon surfaces 被引量:1
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作者 Ruozhong Han Yuchan Zhang +6 位作者 Qilin Jiang Long Chen Kaiqiang Cao Shian Zhang Donghai Feng Zhenrong Sun Tianqing Jia 《Opto-Electronic Science》 2024年第3期33-46,共14页
Femtosecond laser-induced periodic surface structures(LIPSS)have been extensively studied over the past few decades.In particular,the period and groove width of high-spatial-frequency LIPSS(HSFL)is much smaller than t... Femtosecond laser-induced periodic surface structures(LIPSS)have been extensively studied over the past few decades.In particular,the period and groove width of high-spatial-frequency LIPSS(HSFL)is much smaller than the diffraction limit,making it a useful method for efficient nanomanufacturing.However,compared with the low-spatial-frequency LIPSS(LSFL),the structure size of the HSFL is smaller,and it is more easily submerged.Therefore,the formation mechanism of HSFL is complex and has always been a research hotspot in this field.In this study,regular LSFL with a period of 760 nm was fabricated in advance on a silicon surface with two-beam interference using an 800 nm,50 fs femtosecond laser.The ultrafast dynamics of HSFL formation on the silicon surface of prefabricated LSFL under single femtosecond laser pulse irradiation were observed and analyzed for the first time using collinear pump-probe imaging method.In general,the evolution of the surface structure undergoes five sequential stages:the LSFL begins to split,becomes uniform HSFL,degenerates into an irregular LSFL,undergoes secondary splitting into a weakly uniform HSFL,and evolves into an irregular LSFL or is submerged.The results indicate that the local enhancement of the submerged nanocavity,or the nanoplasma,in the prefabricated LSFL ridge led to the splitting of the LSFL,and the thermodynamic effect drove the homogenization of the splitting LSFL,which evolved into HSFL. 展开更多
关键词 laser-induced periodic surface structures(LIPSS) local field enhancement collinear pump-probe imaging silicon high spatial frequency periodic structures
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Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020 被引量:1
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作者 Shi-Guang Wei Lin Li +3 位作者 Kun-Dong Bai Zhi-Feng Wen Jing-Gang Zhou Qin Lin 《Plant Diversity》 SCIE CAS CSCD 2024年第1期70-77,共8页
Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest chang... Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure. 展开更多
关键词 Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest
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Estimation-free spatial-domain image reconstruction of structured illumination microscopy 被引量:1
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作者 Xiaoyan Li Shijie Tu +4 位作者 Yile Sun Yubing Han Xiang Hao Cuifang kuang Xu Liu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期45-58,共14页
Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditiona... Structured illumination microscopy(SIM)achieves super-resolution(SR)by modulating the high-frequency information of the sample into the passband of the optical system and subsequent image reconstruction.The traditional Wiener-filtering-based reconstruction algorithm operates in the Fourier domain,it requires prior knowledge of the sinusoidal illumination patterns which makes the time-consuming procedure of parameter estimation to raw datasets necessary,besides,the parameter estimation is sensitive to noise or aberration-induced pattern distortion which leads to reconstruction artifacts.Here,we propose a spatial-domain image reconstruction method that does not require parameter estimation but calculates patterns from raw datasets,and a reconstructed image can be obtained just by calculating the spatial covariance of differential calculated patterns and differential filtered datasets(the notch filtering operation is performed to the raw datasets for attenuating and compensating the optical transfer function(OTF)).Experiments on reconstructing raw datasets including nonbiological,biological,and simulated samples demonstrate that our method has SR capability,high reconstruction speed,and high robustness to aberration and noise. 展开更多
关键词 structured illumination microscopy image reconstruction spatial domain digital micromirror device(DMD)
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Design Strategies for Aqueous Zinc Metal Batteries with High Zinc Utilization: From Metal Anodes to Anode-Free Structures 被引量:1
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作者 Xianfu Zhang Long Zhang +2 位作者 Xinyuan Jia Wen Song Yongchang Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期305-349,共45页
Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low re... Aqueous zinc metal batteries(AZMBs)are promising candidates for next-generation energy storage due to the excellent safety, environmental friendliness, natural abundance, high theoretical specific capacity, and low redox potential of zinc(Zn) metal. However,several issues such as dendrite formation, hydrogen evolution, corrosion, and passivation of Zn metal anodes cause irreversible loss of the active materials. To solve these issues, researchers often use large amounts of excess Zn to ensure a continuous supply of active materials for Zn anodes. This leads to the ultralow utilization of Zn anodes and squanders the high energy density of AZMBs. Herein, the design strategies for AZMBs with high Zn utilization are discussed in depth, from utilizing thinner Zn foils to constructing anode-free structures with theoretical Zn utilization of 100%, which provides comprehensive guidelines for further research. Representative methods for calculating the depth of discharge of Zn anodes with different structures are first summarized. The reasonable modification strategies of Zn foil anodes, current collectors with pre-deposited Zn, and anode-free aqueous Zn metal batteries(AF-AZMBs) to improve Zn utilization are then detailed. In particular, the working mechanism of AF-AZMBs is systematically introduced. Finally, the challenges and perspectives for constructing high-utilization Zn anodes are presented. 展开更多
关键词 Aqueous zinc metal batteries Zinc anodes High zinc utilization Depth of discharge Anode-free structures
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