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A review of the surface activation and modification of biochars
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作者 Zhang Yihan Chen Longyi 《新型炭材料(中英文)》 北大核心 2026年第1期67-90,共24页
Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellen... Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed. 展开更多
关键词 Activation and modification Carbon material interface surface functionalization Metal nanoparticle deposition surface defect
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A standardized dataset of CO-TPD spectra on transitionmetal single-crystal surfaces
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作者 YANG Lin WU Jianghong WANG He 《燃料化学学报(中英文)》 北大核心 2026年第4期180-190,共11页
Temperature-programmed desorption(TPD)is a fundamental technique in surface science and heterogeneous catalysis for characterizing adsorption behavior,and for extracting key parameters such as adsorption energy.Howeve... Temperature-programmed desorption(TPD)is a fundamental technique in surface science and heterogeneous catalysis for characterizing adsorption behavior,and for extracting key parameters such as adsorption energy.However,the majority of existing TPD data is accessible in the form of published images,which lacks structured and quantitative datasets.This constrains its utility for rigorous quantitative analysis and computational modelling.Using carbon monoxide(CO)which is a widely adopted probe molecule,a curated and standardized dataset of CO-TPD is constructed,encompassing 14 transition-metal single-crystal surfaces,including copper(Cu)and ruthenium(Ru).By systematically extracting numerical data points from published spectra and applying normalization,essential spectral features such as peak shape are fully preserved.The dataset also documents relevant experimental parameters,including heating rates,and was developed using a standardized protocol for data collection and quality control.This resource serves as both a reference library to support the deconvolution of TPD spectra from complex catalysts and an experimental benchmark for calibrating parameters in theoretical models.By providing a reliable and accessible data function,this work advances the microscopic understanding and the rational design of catalyst active centers. 展开更多
关键词 CO-TPD standardized dataset transition metal single-crystal surfaces
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Theoretical insights into the hydrogen peroxide oxidation and reduction reactions on low-index Pt surfaces
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作者 WANG Qi CHEN Lifang +1 位作者 DING Ruimin YIN Xi 《燃料化学学报(中英文)》 北大核心 2026年第1期35-45,共11页
Hydrogen peroxide(H_(2)O_(2))oxidation and reduction reactions(HPOR/HPRR)are pivotal in various innovative electrochemical energy conversion devices.A comprehensive understanding of these mechanisms is critical for ca... Hydrogen peroxide(H_(2)O_(2))oxidation and reduction reactions(HPOR/HPRR)are pivotal in various innovative electrochemical energy conversion devices.A comprehensive understanding of these mechanisms is critical for catalyst design and performance improvement in these applications.In this work,we systematically investigate the HPOR/HPRR mechanisms on low-index Pt surfaces,specifically Pt(111),Pt(100)and Pt(110),through density functional theory(DFT)calculations combined with the computational hydrogen electrode(CHE)model.For HPOR,all the low-index Pt surfaces exhibit a unified potential-determining step(PDS)involving the electrochemical oxidation of hydroperoxyl intermediates(HOO*).The binding free energy of HOO*(Δ_(GHOO*))emerges as an activity descriptor,with Pt(110)exhibiting the highest HPOR activity.The HPRR mechanism follows a chem-electrochemical(C-EC)pathway.The rate-determining step(RDS)of HPRR is either the cleavage of the HO-OH bond(chemical)or the reduction of HO(electrochemical),depending on their respective activation energies.These activation energies are functions of the HO*binding free energy,Δ_(GHO*),establishingΔ_(GHO*)as the descriptor for HPRR activity prediction.Pt(111)and Pt(100)are identified as the most active HPRR catalysts among the studied metal surfaces,although they still experience a significant overpotential.The scaling relationship betweenΔ_(GHOO*)andΔ_(GHO*)reveals a thermodynamic coupling of HPOR and HPRR,explaining their occurrence on Pt surfaces.These findings provide important insights and activity descriptors for both HPOR and HPRR,providing valuable guidance for the design of electrocatalysts in H_(2)O_(2)-related energy applications and fuel cells. 展开更多
关键词 HPOR HPRR Pt low-index surfaces density functional theory
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Assessing Surface Roughness between Unishade and Conventional Composite Resins after Immersion in Different Staining Solutions: An In-Vitro Study
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作者 Sultan Binalrimal Abdullah M.Alshehri +3 位作者 Mohammed Mustafa Ali Robaian Alqahtani Rasha Alharthi Basil Almutairi 《Journal of Polymer Materials》 2026年第1期328-341,共14页
Composite resin restorations are routinely exposed to acidic and chromogenic beverages that may alter their surface integrity over time.This in-vitro study evaluated the surface roughness behavior of two universal sin... Composite resin restorations are routinely exposed to acidic and chromogenic beverages that may alter their surface integrity over time.This in-vitro study evaluated the surface roughness behavior of two universal single-shade(Unishade)composites and two conventionalmulti-shade composites following immersion in commonly consumed staining solutions and assessed whether repolishing could restore smoothness after degradation.A total of 120 standardized disc specimens were fabricated and allocated to fourmaterial groups,with each group subdivided into distilled water,cola,and coffee immersion subgroups.Surface roughness was recorded at baseline,after one week,after one month,and following a final repolishing step using a standardized multi-step system.The findings demonstrated that Unishade composites exhibited more stable surface characteristics across all immersion periods,with changes consistently remaining below the threshold associated with biofilm accumulation.Conventional composites showed greater variability,particularly in cola,where roughness values increased significantly compared with distilled water and coffee.Repolishing substantially reduced immersion-induced roughness in all materials,although its effectiveness varied depending on composite formulation and beverage acidity.Cola produced the greatest surface alterations across all groups,highlighting the erosive potential of low-pH beverages.These results indicate that Unishade composites possess superior resistance to surface degradation,likely due to their nano-structured filler configuration and less hydrophilic resin matrices,while conventional materials appear more susceptible to acidic challenge.Within the limitations of this study,selecting surface-stable material types and applying appropriate finishing and repolishing protocols may enhance the long-term performance and esthetics of composite restorations. 展开更多
关键词 Composite resins surface integrity surface roughness surface damage staining solutions
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Marine Shell-Inspired Laser Surface Texturing:Characterizing the Surface Properties of Co-Based Alloy
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作者 Şefika Kasman Sertan Ozan 《Journal of Bionic Engineering》 2026年第1期341-353,共13页
This study investigated surface roughness,the wettability behavior,and surface energy of Co-based alloy specimens textured using the biomimetic Laser Surface Texturing(LST)method.The surface texture was inspired by th... This study investigated surface roughness,the wettability behavior,and surface energy of Co-based alloy specimens textured using the biomimetic Laser Surface Texturing(LST)method.The surface texture was inspired by the patterns found on marine shells.The impacts of the parameters on wettability,Surface Free Energy(SFE),surface topography,and texture roughness generated by the laser beam tracking a spiral path were investigated.Reducing spiral pitch produces more complicated and chaotic surface patterns.Most surfaces are hydrophobic,and surface roughness and topography influence the Contact Angle(CA).Topography and roughness were affected by frequency and scanning speed;a decrease in scanning speed and frequency generated more chaotic and irregular surface textures.With general factorial analysis and Analysis of Variance(ANOVA),our statistical study reveals that accounting for 88%of the influence,the scanning speed is the primary factor influencing surface roughness.On the other hand,the spiral pitch is essential for defining the struc-tural features of the surface,even if it less influences roughness.The SFE of laser-textured CoCr28Mo alloy specimens was optimizable within the range of 14-32 mN/m.The relevant findings offer valuable insights into optimizing LST for the specific surface properties of the Co-based alloy. 展开更多
关键词 Bio-inspired surface CoCr28Mo alloy WETTABILITY surface roughness surface free energy
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Spatiotemporal variations of surface water and its response to climate change in global arid regions during 2000–2020
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作者 TIAN Yanjun SUN Yongqi +2 位作者 HOU Senlei GAO Yongnian ERKIN Shireli 《Journal of Arid Land》 2026年第4期568-583,共16页
Surface water plays an essential role in the ecohydrological cycle,especially in water-scarce regions.Changes in surface water restrict social,economic,and agricultural development.However,the patterns and underlying ... Surface water plays an essential role in the ecohydrological cycle,especially in water-scarce regions.Changes in surface water restrict social,economic,and agricultural development.However,the patterns and underlying causes of surface water changes over varying frequencies in global arid regions remain unclear.Thus,this study investigated the changes in surface water and the underlying causes using the trend analysis and Spearman correlation coefficient on the basis of multi-source remote sensing and climate datasets across global arid regions during 2000–2020.The surface water was divided into temporary surface water(TSW),seasonal surface water(SSW),and permanent surface water(PSW)by calculating the surface water inundation frequency.Considering that surface water may be influenced by precipitation in the upper basins,we analyzed the response of surface water area to climatic factors at the basin scale.The area of all surface water(ASW)increased dramatically in global arid regions from 2000 to 2020,increasing from 61.88×104 to 67.40×104 km^(2);however,this increase was accompanied by a decrease in surface water inundation frequency.TSW increased by 55.46%relative to its area in 2000,with a net change rate of 3284.00 km^(2)/a.Changes in surface water were predominantly observed in the Kyzylkum Desert in Central Asia,the Thar Desert in southwestern Asia,and the deserts in Oceania.Precipitation had a significant effect on SSW and TSW at the basin scale.The correlation between precipitation and SSW area can reach 0.808 in the Indus River Basin of the Thar Desert(P<0.01).The findings provide a more comprehensive understanding of surface water variability in global arid regions,carrying significant practical implications for the scientific management of surface water at different frequencies. 展开更多
关键词 surface water area surface water inundation frequency temporary surface water climate change snow melting global arid regions
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The surface binding and energy issues in the rational design of separators for Li||S batteries
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作者 Hongfang Du Lijing Wang +8 位作者 Shuyu Cheng Chao Wu Sheng Yang Yang Liu Yi Zhao Dandan Cui Shaowei Zhang Shixue Dou Liangxu Lin 《Journal of Energy Chemistry》 2026年第1期987-1013,I0021,共28页
Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been d... Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been demonstrated to be one of the most efficient and cost-effective strategies to curb the shuttle effect,and tremendous research progress has been achieved.The efficiency of a separator depends on its interaction with LiPSs,which is governed by the surface energy and binding strength.Despite several review works that have been reported to advance the separators,most of them primarily focus on active material innovation and construction.The most crucial issues of surface binding energy have not been systematically reviewed,limiting the precise design of efficient separators.In this review,fundamentals related to surface energy and binding interactions with LiPSs are comprehensively analyzed and discussed.With surface binding and energy main lines,the advancements in separator engineering strategies are elaborately summarized and discussed.Moreover,techniques for evaluating affinity to LiPSs are thoroughly analyzed to avoid any ambiguities in measurement.Based on the research context,valuable research directions are suggested to construct efficient separators.This work provides guidelines to regulate the surface binding and energy of separators for high-performance LSBs. 展开更多
关键词 Lithium-sulfur batteries SEPARATOR surface binding affinity surface energy Rational design
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Effect of surface area and pore size on long-term bone regeneration:dynamic changes in geometric characteristics,mass transport,and mechanobiology
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作者 Xing Peng Guoxian Zhang +5 位作者 Jian Pu Shu Yang Wen Cui Xue Zhou Shuxin Qu Zhongmin Jin 《Bio-Design and Manufacturing》 2026年第1期137-152,I0021,共17页
The specific surface area(S S)and pore size(D)exhibit an inherent trade-off in the microscale design of bone implants:larger pores typically correlate with reduced surface area and vice versa.This relationship has att... The specific surface area(S S)and pore size(D)exhibit an inherent trade-off in the microscale design of bone implants:larger pores typically correlate with reduced surface area and vice versa.This relationship has attracted notable attention because of its critical role in the regulation of cell adhesion and osteogenesis.However,it remains largely unclear how S S and D affect the generated bone tissue and dynamically change during long-term osteogenesis.Herein,by applying rigorous geometric mapping to minimal surfaces,we constructed precisely partitioned and layer-by-layer thickened tissue models to simulate osteogenesis across different temporal scales and thereby track the dynamic evolution of geometric characteristics,permeability,and mechanobiological tissue differentiation.The high-S S samples were found to facilitate the rapid formation of new bone tissue in the early stages.However,their smaller pores tended to cause occlusions,hindering further tissue development.In contrast,low-S S samples showed slower bone regeneration,but their larger pores provided adequate physical space for tissue regeneration and mass transport,ultimately promoting bone formation in the long term.Mechanobiological regulation suggests that fibrous tissue formation inhibits additional bone formation,establishing a dynamic equilibrium between osteogenesis and pore space to sustain nutrient/waste exchange throughout the regenerative process.Overall,smaller pores are preferable in implants for minimally loaded osteoplasty procedures focused on early-stage bone consolidation,whereas larger pores are preferable in dynamically loaded implants requiring prolonged mechanical stability. 展开更多
关键词 Minimal surface Specific surface area Pore size Bone ingrowth MECHANOBIOLOGY Finite element simulation
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Path planning of unmanned surface vehicles based on improved particle swarm optimization algorithm with consideration of particle sight distance
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作者 WANG Cheng YANG Junnan +3 位作者 ZHANG Xinyang QIAN Zhong ZHU Ye LIU Hong 《上海海事大学学报》 北大核心 2026年第1期9-19,共11页
To enhance the accuracy of path planning of unmanned surface vehicles(USVs),the particle swarm optimization algorithm(PSO)is improved based on species migration strategies observed in ecology.By incorporating the conc... To enhance the accuracy of path planning of unmanned surface vehicles(USVs),the particle swarm optimization algorithm(PSO)is improved based on species migration strategies observed in ecology.By incorporating the concept of particle sight distance,an improved algorithm,called SD-IPSO,is proposed for the real-time autonomous navigation of USVs in marine environments.The algorithm refines the individual behavior pattern of particles in the population,effectively improving both local and global search capabilities while avoiding premature convergence.The effectiveness of the algorithm is validated using standard test functions from CEC-2017 function library,assessing it from multiple dimensions.Sensitivity analysis is conducted on key parameters in the algorithm,including particle sight distance and population size.Results indicate that compared with PSO,SD-IPSO demonstrates significant advantages in optimization accuracy and convergence speed.The application of SD-IPSO in path planning is further investigated through a 14-point traveling salesman problem(TSP)example and navigation autonomous tests of USVs in marine environments.Findings demonstrate that the proposed algorithm exhibits superior optimization capabilities and can effectively address the path planning challenges of USVs. 展开更多
关键词 particle swarm optimization algorithm(PSO) sight distance unmanned surface vehicle(USV)
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Optimization of catalytic steam gasification for hydrogen production:response surface methodology approach
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作者 Ayisha Naziba Thaha Karthikeyan Subburamu +3 位作者 Djanaguiraman Maduraimuthu Kamaraj A Palaniselvam Vellaichamy Ramesh Desikan 《Clean Energy》 2026年第1期78-93,共16页
The current investigation delves into the process of the optimization of hydrogen production via catalytic steam gasification within a fixed-bed downdraft gasifier.This study optimized hydrogen-rich syngas production ... The current investigation delves into the process of the optimization of hydrogen production via catalytic steam gasification within a fixed-bed downdraft gasifier.This study optimized hydrogen-rich syngas production from biomass by using catalytic steam gasification in a fixed-bed reactor.Response surface methodology with a Box-Behnken design was employed to model the effects of the steam-to-biomass ratio(1-3),nanocatalyst loading(5-15 wt%),and airflow rate(20-40 L min^(−1))on syngas yield and hydrogen content.The derived quadratic model was highly significant,with optimization identifying an airflow rate of 30 L min^(−1),steam-to-biomass ratio of 3.0,and nanocatalyst loading of 5 wt%as the ideal conditions.Experimental validation under these parameters confirmed the excellent predictive capability of the model,yielding 1.69 m^(3)kg^(−1)of syngas with a high hydrogen content of 65.9% along with carbon monoxide of 13.2%,carbon dioxide of 8.6%,and methane of 1.3%.This represented a substantial enhancement over conventional air gasification,which produced only 1.52 m^(3)kg^(−1)syngas with 16.2%H_(2).The optimized catalytic steam-gasification process achieved a cold gas efficiency of 82.5%and a hydrogen yield of 108.8 g kg^(−1)of biomass,driven by the synergistic effect of steam and the nanocatalyst in promoting tar cracking and reforming reactions.The resulting syngas had a heating value of 11.49 MJ Nm^(−3).These results demonstrate that the response-surface-methodology-guided optimization of nanocatalytic steam gasification is a highly effective strategy for producing a high-quality,hydrogen-rich syngas,marking a significant improvement in process efficiency for sustainable energy applications. 展开更多
关键词 surface methodology catalytic steam gasification hydrogen production NANOCATALYST response surface methodology hydrogen content box behnken design syngas yield
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Erratum:Marine Shell-Inspired Laser Surface Texturing:Characterizing the Surface Properties of Co-Based Alloy
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作者 Sefika Kasman Sertan Ozan 《Journal of Bionic Engineering》 2026年第1期551-551,共1页
The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Sur... The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Surfaces",line 2:The device name was corrected from"YDFLP-E-50-M8"to"YDFLP-50-M8."Page 3,Section 2.4:The phrase"95%confidence interval"has been corrected to"95%confidence level."Page 3,Figure 1 caption:The phrase"fandg"has been corrected to"f and g."The order"C4 and C12"has been reversed to"C12 and C4,"in accordance with the display order in the figure.Page 4,Figure reference:The phrase"Figs.4c and d"has been corrected to"Figs.5b and c."Page 5,paragraph starting with"The ANOVA results are presented...":The phrase"95%confidence interval"has been corrected to"95%confidence level." 展开更多
关键词 laser surface texturing surface properties marine shell inspired co based alloy laser texturing procedure confidence level ANOVA results
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Geodetic Techniques for Climate-Induced Surface Deformation:A Global Review
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作者 Chang Yu Tiexin Lv 《Journal of Environmental & Earth Sciences》 2026年第1期224-241,共18页
Climate change is causing extensive and quantifiable surface deformation by moving mass in the cryosphere,hydrosphere,atmosphere,and oceans.These deformations can give a great deal of information on the dynamics of th... Climate change is causing extensive and quantifiable surface deformation by moving mass in the cryosphere,hydrosphere,atmosphere,and oceans.These deformations can give a great deal of information on the dynamics of the Earth system and interactions between climate processes and solid Earth processes.Global Navigation Satellite Systems(GNSS),Interferometric Synthetic Aperture Radar(InSAR),satellite gravimetry,and other supplementary techniques have become important tools to be used to monitor and quantify these deformations.The insight of this review is the understanding of the mechanisms that cause deformation on the surface due to climate change,the strengths and weaknesses of the modern geodetic observation methods,and the way in which these geodetic observations are reconciled with the Earth’s response models and climate simulations.Polar,alpine,hydrologically sensitive,and coastal case studies demonstrate that geodesy can be used globally in climate change studies.Although there has been a lot of improvement,there have been many problems in signal separation,data coverage,and uncertainties in models,but new emerging technologies are promising solutions.A combined climate/geodetic observing system will be critical in enhancing long-term monitoring and in further developing the knowledge on how the Earth responds to climate change. 展开更多
关键词 Climate Change surface Deformation GEODESY GNSS INSAR
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Visual Servo-Based Formation Control of Unmanned Surface Vehicles
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作者 Xiang Liu Yueying Wang +1 位作者 Xudong Zhao Zhiguang Feng 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期480-482,共3页
Dear Editor,This letter addresses the formation control problem for unmanned surface vehicles(USVs)under GPS-denied environments.A novel visual servo formation control scheme,utilizing a monocular camera on the follow... Dear Editor,This letter addresses the formation control problem for unmanned surface vehicles(USVs)under GPS-denied environments.A novel visual servo formation control scheme,utilizing a monocular camera on the follower to obtain the leader’s global position,is developed,which is also capable of guaranteeing collision avoidance and visibility maintenance(CA&VM)raised by the requirement of actual formation navigation. 展开更多
关键词 visual servo formation control collision avoidance formation navigation unmanned surface vehicles usvs monocular camera unmanned surface vehicles formation control visual servo
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Kinematics and directionality of body turning in water striders (Gerris argentatus) on the water surface
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作者 Javad Meshkani Hamed Rajabi +1 位作者 Alexander Kovalev Stanislav N.Gorb 《Insect Science》 2026年第1期298-312,共15页
Water striders inhabit the elastic surface tension film of water, sharing their environment with other aquatic organisms. Their survival relies heavily on swift maneuverability and navigation around floating obstacles... Water striders inhabit the elastic surface tension film of water, sharing their environment with other aquatic organisms. Their survival relies heavily on swift maneuverability and navigation around floating obstacles, which aids in the exploration of their habitat and in escaping from potential threats. Their high agility is strongly based on the ability to execute precise turns, enabling effective directional control. This paper investigates the intricate coordination of leg movements essential for initiating and sustaining turning maneuvers in water striders. We elucidate the distinct roles of each leg in modulating posture and stability during turns, with a focus on the pivotal role of the midlegs in maintaining directional movement. Through analysis of leg accelerations, decelerations, and load distribution, we unveil the spatiotemporal dynamics governing successful turns. Our findings reveal refined turning strategies employed by water striders in varying situations, from narrow to wide turns, characterized by adaptations in their locomotor system, particularly in the widening of the sculling field. Additionally, we report the phenomenon of reverse sculling, a novel escape tactic of water striders. By shedding light on the maneuverability of water striders, this study contributes to a deeper understanding of animal locomotion strategies in aquatic environments. 展开更多
关键词 aquatic insects BIOMECHANICS HETEROPTERA locomotion ROWING surface tension
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Surface/Interface Engineering for High‑Resolution Micro‑/Nano‑Photodetectors
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作者 Jinlin Chang Ting Liu +7 位作者 Xiao Geng Genting Dai Liangliang Yang Mingjun Cheng Linpan Jiang Zhenyuan Sun Jianshe Liu Wei Chen 《Nano-Micro Letters》 2026年第3期499-553,共55页
Photodetectors can convert light energy into electrical signals,so are widely used in photovoltaics,photon counting,monitoring,and imaging.Photodetectors are easy to prepare high-resolution photochips because of their... Photodetectors can convert light energy into electrical signals,so are widely used in photovoltaics,photon counting,monitoring,and imaging.Photodetectors are easy to prepare high-resolution photochips because of their small size unit integration.However,these photodetector units often exhibit poor photoelectric performance due to material defects and inadequate structures,which greatly limit the functions of devices.Designing modification strategies and micro-/nanostructures can compensate for defects,adjust the bandgap,and develop novel quantum structures,which consequently optimize photovoltaic units and revolutionize optoelectronic devices.Here,this paper aims to comprehensively elaborate on the surface/interface engineering scheme of micro-/nano-photodetectors.It starts from the fundamentals of photodetectors,such as principles,types,and parameters,and describes the influence of material selection,manufacturing techniques,and post-processing.Then,we analyse in detail the great influence of surface/interface engineering on the performance of photovoltaic devices,including surface/interface modification and micro-/nanostructural design.Finally,the applications and prospects of optoelectronic devices in various fields such as miniaturization of electronic devices,robotics,and human–computer interaction are shown. 展开更多
关键词 PHOTODETECTORS surface modification HIGH-RESOLUTION Micro-/nanostructures
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Construction of Bionic Non-Smooth Surface of Cu-Based Friction Materials Based on Finite Element Method
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作者 Lekai Li Juxiang Zhu +3 位作者 Zhaohua Yao Mengting Xing Yitong Tian Ma Yunhai 《Journal of Bionic Engineering》 2026年第1期326-340,共15页
To solve the problem of abnormal abrasion of Cu-Based Friction Materials(CBFMs),Bionic Non-Smooth Surface(BNS)on friction surface of CBFMs was constructed based on bionic principles,and the optimal bionic prototype wa... To solve the problem of abnormal abrasion of Cu-Based Friction Materials(CBFMs),Bionic Non-Smooth Surface(BNS)on friction surface of CBFMs was constructed based on bionic principles,and the optimal bionic prototype was selected by Finite Element Method(FEM).In addition,the bionic parameters were optimized by Response Surface Method(RSM).Samples holding BNS were prepared by Laser Processing,tribological properties were tested by a Friction and Wear Tester and worn surface morphology was characterized by a Scanning Electron Microscope(SEM).The results showed that BNS on friction surface could regulate the stress distribution and alleviate the peak stress.Among all samples,the coupled texture of pit-hexagonal got the minimum peak stress.During braking,bionic texture could also collect wear debris or change the motion forms from sliding to rotation,which can reduce abnormal abrasion.The wear rate was reduced by 19.31%.The results in this paper can provide a new idea for enhancing the tribological properties of CBFMs,and can also lay the foundation for further research of bionic tribology. 展开更多
关键词 Bionic non-smooth surface Friction materials FEM Wear mechanism
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Thermodynamic Correlation Between Surface Carboxyl Configuration and Wettability
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作者 GUO Zhuohuan WANG Dayang 《高等学校化学学报》 北大核心 2026年第1期255-266,共12页
In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using at... In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using attenuated total reflectance Fourier-transform infrared spectroscopy(ATR-FTIR),the molecular configurations of surface carboxyl groups(COOH),free carboxyl(COOH_(f))and hydrogen-bonded carboxyl(COOH_(HB),were directly correlated with the polar component of surface energy(γ^(s,p)).By decomposing theγ^(s,p)values of the PAA thin films as a sum of the contributions of COOH_(f)and COOH_(H B),the intrinsic polar component of surface energy of COOH_(H B)(γ_(H B)^(s,p*))was quantified for the first time as 8.34 mN/m,significantly lower than that of COOH_(f)(γ_(f)^(s,p*)=34 mN/m).This result highlights that hydrogen bonding markedly reduces theγ^(s,p),providing a rational explanation for the relatively large water contact angle observed on PAA thin films.Furthermore,it establishes a thermodynamic basis for estimating the fraction of surface COOH_(H B)groups(f H B)from wettability measurements.Further extension of the model to carboxyl-terminated self-assembled monolayers(COOH-SAMs)revealed that surface COOH density(ΣCOOH)critically regulates wetting behavior:whenΣCOOH ranges from 4.30 to 5.25 nm^(-2),COOH groups predominantly exist in a free state and facilitate effective hydration layers,thereby promoting superhydrophilicity.Overall,this study not only establishes a unified thermodynamic framework linking surface COOH configurations to macroscopic wettability,but also validates its universality by extending it to COOH-SAMs systems,thereby providing a unified theoretical framework for the controllable design of hydrophilicity in various COOH-functionalized surfaces. 展开更多
关键词 Polyacrylic acid film Hydrogen bonding Attenuated total reflectance Fourier-transform infrared spectroscopy Quantitative carboxyl configuration Polar component of surface energy
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Radar cross section reduction in target airspace based on ultra-wide-angle artificial electromagnetic absorbing surface
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作者 LI Liang GAO Hongwei +1 位作者 ZHANG Binchao JIN Cheng 《Journal of Systems Engineering and Electronics》 2026年第1期75-83,共9页
A methodology for the reduction of radar cross section(RCS)of cambered platforms within the target airspace is presented,which utilizes a dual-polarized ultra-wide-angle artificial electromagnetic absorbing surface.By... A methodology for the reduction of radar cross section(RCS)of cambered platforms within the target airspace is presented,which utilizes a dual-polarized ultra-wide-angle artificial electromagnetic absorbing surface.By applying the theory of generalized Brewster complex wave impedance matching,five distinct unit cell designs are developed to attain more than95%absorption rate for dual-polarized incident waves within five angular ranges:0°-30°,30°-50°,50°-60°,60°-70°,and 70°-80°.To optimally reduce the RCS of a cambered platform,the five types of units can be evenly distributed on the surface based on the local incident angles of plane waves originating from the target airspace.As an illustrative example,the leading edge of an airfoil is taken into account,and experimental measurements validate the efficiency of the proposed structure.Specifically,the absorbing surface achieves more than 10 dB of RCS reduction in the frequency ranges from 5-10 GHz(about66.7%relative bandwidth)for dual polarizations. 展开更多
关键词 artificial electromagnetic absorbing surface DUAL-POLARIZATION oblique incidence ultra-wide-angle
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Fungi on the cuticle surface increase the resistance of Aedes albopictus to deltamethrin
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作者 Ju-Ping Hu Si-Jia Deng +5 位作者 Lin Gu Lin Li Lei Tu Ju-Lin Li Jian-Xia Tang Guo-Ding Zhu 《Insect Science》 2026年第1期250-270,共21页
Aedes albopictus(Ae.albopictus)is widely distributed and can transmit many infectious diseases,and insecticide-based interventions play an important role in vector control.However,increased insecticide resistance has ... Aedes albopictus(Ae.albopictus)is widely distributed and can transmit many infectious diseases,and insecticide-based interventions play an important role in vector control.However,increased insecticide resistance has become a severe public health problem,and the clarification of its detailed mechanism is a matter of urgence.This study found that target-site resistance and metabolic resistance could not fully explain insecticide resistance in field Ae.albopictus,and there were likely other resistance mechanisms involved.The 16S and internal transcribed spacer sequencing revealed significant differences in the species compositions of the cuticle surface symbiotic bacteria and fungi between deltamethrin(DM)-resistant(DR)and DM-susceptible(DS)Ae.albopictus.Additionally,the abundances of Serratia spp.and Candida spp.significantly increased after DM treatment.Furthermore,2 fungi(Rhodotorula mucilaginosa and Candida melibiosica)and 3 bacteria(Serratia marcescens,Klebsiella aerogenes,and Serratia sp.)isolated from DR Ae.albopictus can use DM as their sole carbon source.After reinoculation onto the cuticle surface of DS Ae.albopictus,R.mucilaginosa and C.melibiosica significantly enhanced the DM resistance of Ae.albopictus.Moreover,transcriptome sequencing of the surviving Ae.albopictus after DM exposure revealed that the gene expression of cytochrome P450 enzymes and glutathione-S-transferases increased,suggesting that besides the direct degradation,the candidate degrading microbes could also cause insecticide resistance via indirect enhancement of mosquito gene expression.In conclusion,we demonstrated that the cuticle surface symbiotic microbes were involved in the development of insecticide resistance in Ae.albopictus,providing novel and supplementary insights into insecticide resistance mechanisms. 展开更多
关键词 Aedes albopictus cuticle surface symbiotic deltamethrin resistance FUNGI
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