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Surface micro-texture on sapphire fabricated by laser ablation trajectory regulation 被引量:1
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作者 Quanli ZHANG Qiwen WANG +2 位作者 Zhen ZHANG Yucan FU Jiuhua XU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第3期525-536,共12页
Fabrication of the surface micro-texture on the C-plane sapphire is undertaken by a355 nm Ultraviolet(UV)pulsed laser.The surface micro-textures of sapphire with different laser scanning line spacing ranging from 10 l... Fabrication of the surface micro-texture on the C-plane sapphire is undertaken by a355 nm Ultraviolet(UV)pulsed laser.The surface micro-textures of sapphire with different laser scanning line spacing ranging from 10 lm to 100 lm are obtained,where the selection range of scanning line spacing is controlled in the range of the groove width and plasma width to obtain a surface of high Peak-Valley(PV)value.A reasonable processing order is proposed to manufacture different types of surface micro-textures on sapphire by laser ablation trajectory regulation.In the multiple-passes laser ablation of sapphire by the UV nanosecond pulsed laser,the scanning lines in each direction is treated as once scanning.On this basis,the multiple processing can be carried out to avoid the influence of the subsequent scanning on the machined groove.In addition,the effect of different scanning line spacing on the PV value is quantified and different types of surface microtextures on sapphire,including the squares,the rhombuses and the hexagons,are successfully fabricated,which can be applied in the friction reduction or anti-reflection field. 展开更多
关键词 Laser ablation trajectory SAPPHIRE Scanning line spacing surface micro-texture PV values
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Grain size and surface micro-texture characteristics and their paleoenvironmental significance of Holocene sediment in southern margin of the Gurbantunggut Desert,China
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作者 MA Yunqiang LI Zhizhong +2 位作者 TAN Dianjia ZOU Xiaojun TAO Tonglian 《Journal of Arid Land》 SCIE CSCD 2024年第5期632-653,共22页
The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant imp... The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant importance for understanding the interactive processes of wind and water forces,as well as the provenance of sediment.However,there are relatively few investigations on the characteristics of such sediment at present.In this study,we researched three aeolian-alluvial interactive stratigraphic profiles and different types of surface sediment on the desert-oasis transitional zone of southern margin of the Gurbantunggut Desert.Based on the optically stimulated luminescence(OSL)dating of aeolian sand and analyses of quartz sand grain size and surface micro-texture,we explored the aeolian-alluvial environmental change at southern margin of the desert in Holocene,as well as the provenance of sediment.The results indicated that the grain size characteristics of different types of sediment in the stratigraphic profiles were similar to those of modern dune sand,interdune sand,muddy desert surface soil,and riverbed sand.Their frequency curves were unimodal or bimodal,and cumulative probability curves were two-segment or three-segment,mainly composed of suspension load and saltation load.The quartz sand in the sediment at southern margin of the desert had undergone alternating transformation of various exogenic forces,with short transportation distance and time,and sedimentary environment was relatively humid.In Holocene,southern margin of the desert primarily featured braided river deposits,and during intermittent period of river activity,there were also aeolian deposits such as sand sheet deposits,stabilized dune deposits,and mobile dune deposits.The provenance for Holocene alluvial deposits at southern margin of the desert remains relatively constant,with the debris of the Tianshan Mountains being the primary provenance.Aeolian sand is mainly near-source recharge,which is formed by in situ deposition of fluvial or lacustrine materials in southern margin of the desert transported by wind erosion,and its provenance was still the weathered debris of the Tianshan Mountains.In addition,the sand in interior of the desert may be transported by northwest wind in desert-scale,thus affecting the development of dunes in southern margin of the desert.The results of this study provide a reference for understanding the composition and provenance changes of desert sand in the context of global climate change. 展开更多
关键词 aeolian-alluvial deposition grain size surface micro-texture sedimentary environment HOLOCENE
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Influences of the Textured Surface Micro-Texture Depth on the Friction Coefficient 被引量:2
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作者 Moussa Magara Traore 《World Journal of Mechanics》 2020年第12期221-228,共8页
The use of textured surfaces in lubrication to improve the tribological characteristics has been widely studied. The understanding of the textured surface geometric parameters influences on these tribological characte... The use of textured surfaces in lubrication to improve the tribological characteristics has been widely studied. The understanding of the textured surface geometric parameters influences on these tribological characteristics could help to improve their applications in industry. In this paper, we purpose to analyze the influence of the micro-texture depth on the friction coefficient experimentally. The experiment is conducted using different copper alloy samples have been the first laser textured with different micro-hole depth (40.83 μm and 46.36 μm). A 3D electronic Olympus microscope is used to visualize the shapes of the holes and find the depths. Then, the friction test has been conducted using these samples with the same velocity. The time variation of the friction coefficient is plotted and analyzed. The analysis of time variation of the friction coefficient shows a reduction of friction coefficient with the increase of the micro-hole depth has been observed. In some cases, this reduction is significant. 展开更多
关键词 Friction Coefficient TRIBOLOGY Textured surfaces
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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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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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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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Experimental Study on the Frosting Characteristics of Corrugated Surfaces under the Influence of Different Surface Properties
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作者 Kai Song Lishan Feng +2 位作者 Shugang Duan Weilong Zhao Haikun Zheng 《Frontiers in Heat and Mass Transfer》 2026年第1期210-227,共18页
This study experimentally investigates the influence of surfacewettability on the frosting characteristics of three types of corrugated structures(Types A,B,and C)under controlled low-temperature conditions.The experi... This study experimentally investigates the influence of surfacewettability on the frosting characteristics of three types of corrugated structures(Types A,B,and C)under controlled low-temperature conditions.The experiments were conducted in a constant-temperature bath at a cold surface temperature of–5℃,relative humidity of 90%,and ambient air temperature of 10℃.The results reveal that the variation trends of frost morphology,frost mass,and frost layer thickness are generally consistent across surfaces with different wettability.Among the tested surfaces,frost crystal formation and complete surface coverage occurred latest on the superhydrophobic surface(CA=153.9–165.8℃),next on the bare aluminumsurface(75.3–83.2℃),and earliest on the hydrophilic surface(5.3–7.5℃).At the same frosting duration,the superhydrophobic surface exhibited a sparse and fluffy frost layer,the bare aluminum surface formed a rough and dense frost,while the hydrophilic surface developed a fine and compact frost layer.The amount of frost formation decreased in the order of hydrophilic>bare aluminum>superhydrophobic,indicating that the superhydrophobic surface provides the most significant anti-frosting effect during the initial stages of frost formation.For instance,on the Type A corrugated structure,after 15 min of frosting,the frost mass on the superhydrophobic surface was 38.78%and 68.45%lower than those on the bare aluminum and hydrophilic surfaces,respectively.After 30 min,these differences were 4.99%and 25.26%,respectively.Overall,the superhydrophobic surface exhibited the smallest frost mass and frost layer thickness,demonstrating superior anti-frosting performance compared with the other surface types. 展开更多
关键词 FROSTING corrugated surface frosting amount superhydrophobic surface
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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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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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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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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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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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Surface hydroxyl enriched ruthenium selenide nanoparticles for efficient seawater hydrogen evolution reaction
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作者 Ming-Xia Hu Le-Wei Shen +11 位作者 Yong Wang Wen-Ying Zhao Kang-Yi Xiong Ling Shen Yi Lu Jie Ying Yu-Xuan Xiao Wei Geng Kenneth IOzoemena Maria Magdalena Titirici Ge Tian Xiao-Yu Yang 《Science China Chemistry》 2026年第2期939-945,共7页
The rationally designed ruthenium selenide(RuSe_(1.6)-500)nanocomposite with selenium vacancies was synthesized via a hydrothermal/annealing approach.During the annealing step,calcination under a H_(2)/Ar atmosphere f... The rationally designed ruthenium selenide(RuSe_(1.6)-500)nanocomposite with selenium vacancies was synthesized via a hydrothermal/annealing approach.During the annealing step,calcination under a H_(2)/Ar atmosphere facilitated the evaporation of selenium,thereby generating selenium vacancies.This study confirmed that RuSe_(1.6)-500 prepared by this method functions as an efficient electrocatalyst for the hydrogen evolution reaction(HER)in seawater.Furthermore,experiments and density functional theory calculations demonstrated that the enhanced electrocatalytic performance and resistance to Cl-induced corrosion in seawater can be attributed to the surface reconstruction of RuSe_(1.6)-500 during the HER process.Specifically,the reconstruction involves the adsorption of hydroxyl groups at selenium vacancies,leading to the formation of a hydroxy-rich surface on RuSe_(1.6)-500.The hydroxy-rich surface is responsible for the superior electrocatalytic activity and stability of RuSe_(1.6)-500 as an electrocatalyst for the HER in seawater. 展开更多
关键词 hydrogen evolution reaction RuSe_x surface reconstruction Se vacancy
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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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Optimized Industrial Surface Defect Detection Based on Improved YOLOv11
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作者 Hua-Qin Wu Hao Yan +3 位作者 Hong Zhang Shun-Wu Xu Feng-Yu Gao Zhao-Wen Chen 《Structural Durability & Health Monitoring》 2026年第1期268-282,共15页
In industrial manufacturing,efficient surface defect detection is crucial for ensuring product quality and production safety.Traditional inspectionmethods are often slow,subjective,and prone to errors,while classicalm... In industrial manufacturing,efficient surface defect detection is crucial for ensuring product quality and production safety.Traditional inspectionmethods are often slow,subjective,and prone to errors,while classicalmachine vision techniques strugglewith complex backgrounds and small defects.To address these challenges,this study proposes an improved YOLOv11 model for detecting defects on hot-rolled steel strips using the NEU-DET dataset.Three key improvements are introduced in the proposed model.First,a lightweight Guided Attention Feature Module(GAFM)is incorporated to enhance multi-scale feature fusion,allowing the model to better capture and integrate semantic and spatial information across different layers,which improves its ability to detect defects of varying sizes.Second,an Aggregated Attention(AA)mechanism is employed to strengthen the representation of critical defect features while effectively suppressing irrelevant background information,particularly enhancing the detection of small,low-contrast,or complex defects.Third,Ghost Dynamic Convolution(GDC)is applied to reduce computational cost by generating low-cost ghost features and dynamically reweighting convolutional kernels,enabling faster inference without sacrificing feature quality or detection accuracy.Extensive experiments demonstrate that the proposed model achieves a mean Average Precision(mAP)of 87.2%,compared to 81.5%for the baseline,while lowering computational cost from6.3Giga Floating-point Operations Per Second(GFLOPs)to 5.1 GFLOPs.These results indicate that the improved YOLOv11 is both accurate and computationally efficient,making it suitable for real-time industrial surface defect detection and contributing to the development of practical,high-performance inspection systems. 展开更多
关键词 YOLOv11 object detection industrial surface defect NEU-DET
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Depression induces ocular surface inflammation and dry eye-like changes in mice
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作者 Xiang Lin Yu-Wen Liu +7 位作者 Jia-Ni Li Wei-Jie Ouyang Li-Ying Tang Jie-Li Wu Zhao-Lin Liu Shi-Nan Wu Jiao-Yue Hu Zu-Guo Liu 《International Journal of Ophthalmology(English edition)》 2026年第3期434-442,共9页
AIM:To investigate the impact of depression-like behavior on ocular surface homeostasis in a mouse model,with a focus on dry eye-like alterations.METHODS:Male C57BL/6J mice(10-12 weeks old)were randomly assigned to co... AIM:To investigate the impact of depression-like behavior on ocular surface homeostasis in a mouse model,with a focus on dry eye-like alterations.METHODS:Male C57BL/6J mice(10-12 weeks old)were randomly assigned to control or restraint stress(RS)groups.The RS group underwent three intermittent 24-hour restraint sessions to induce depressive-like behavior.Behavioral testing,tear secretion measurement,and corneal Oregon Green Dextran(OGD)staining were performed.Postmortem analyses included histological evaluation of lacrimal glands,goblet cell quantification using periodic acid-Schiff staining,and assessment of key inflammatory and apoptotic markers:interleukin(IL)-17,matrix metalloproteinases(MMP)-3,MMP-9,IL-13,interferon(IFN)-γ,and cleaved caspase-3 and-8.RESULTS:Repeated RS induced depression-like behavior and significant ocular surface changes.RStreated mice showed increased corneal OGD uptake and upregulation of gene/protein expression of IL-17,MMP-3,and MMP-9(P<0.05).Goblet cell density and IL-13 protein expression were reduced,while IFN-γprotein expression was elevated(P<0.05).Cleaved caspase-3 and-8 levels were significantly increased in both cornea and conjunctiva.Tear volume and lacrimal gland size were unchanged;however,mild inflammatory infiltration was observed in lacrimal glands.CONCLUSION:Repeated RS leads to ocular surface inflammation and dry eye-like pathology,including corneal barrier disruption,goblet cell loss,and epithelial apoptosis.These findings suggest that depression contributes to the pathogenesis of dry eye disease via immune-mediated mechanisms. 展开更多
关键词 DEPRESSION restraint stress dry eye ocular surface damage INFLAMMATION MICE
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Correlation of ocular surface function with sleep quality,anxiety,and depression in patients with dry eye disease
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作者 Yi-Long Lin Hai-Hua Liu +2 位作者 Shu-Jin Chen Qi-Hua Wan Kai-Ping Zhang 《World Journal of Psychiatry》 2026年第1期256-266,共11页
BACKGROUND Dry eye disease(DED)is a multifactorial ocular surface disorder with rising prevalence.It is closely related to systemic health and psychological factors,such as sleep and mood disorders,which significantly... BACKGROUND Dry eye disease(DED)is a multifactorial ocular surface disorder with rising prevalence.It is closely related to systemic health and psychological factors,such as sleep and mood disorders,which significantly impact the quality of life of patients.AIM To explore the correlations between ocular surface function,sleep quality,and anxiety/depression in patients with DED.METHODS This was a cross-sectional investigative study that included 358 patients with DED between January 2022 and January 2025.Ocular surface was assessed using the ocular surface disease index(OSDI),tear film break-up time,fluorescein staining score,and Schirmer I test.The Pittsburgh Sleep Quality Index(PSQI),Self-Rating Anxiety Scale(SAS),and Self-Rating Depression Scale(SDS)were used to evaluate sleep quality and anxiety/depression levels.Correlation and linear regression analyses were used to explore the relationships.RESULTS The mean PSQI score of the patients was 9.94±2.18;the mean SAS score was 47.30±4.90,and the mean SDS score was 50.08±5.52.These suggested a prevalence of sleep and psychological abnormalities.There was a significant correlation between the indicators of ocular surface function(OSDI,tear film break-up time,fluorescein staining,and Schirmer I test)and PSQI,SAS,and SDS scores(P<0.05).Moreover,multiple regression revealed that age≥50 years(β=1.55,P=0.029),PSQI scores(β=0.58,P<0.001),SAS scores(β=0.17,P=0.017),and SDS scores(β=0.15,P=0.019)were independent predictors of the OSDI scores.CONCLUSION Ocular surface function in patients with DED is closely related to sleep quality and anxiety/depression,emphasizing the need for holistic clinical management. 展开更多
关键词 Dry eye disease Ocular surface function Sleep quality ANXIETY DEPRESSION
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Transmission Characteristics of Biological Pollutant on Cold Surface Through Surface Contact During Cold Storage
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作者 Zhiqiang Wang Lixin Chen +3 位作者 Saiwei Ge Wei Xiao Zhuohao Xuan Pengcheng Zhang 《Journal of Harbin Institute of Technology(New Series)》 2026年第1期20-32,共13页
The cold chain environment is an important route for the long⁃distance transmission of pathogenic micro⁃organisms.In this study,we explored the mechanisms of secondary propagation through surface contact on cold surfa... The cold chain environment is an important route for the long⁃distance transmission of pathogenic micro⁃organisms.In this study,we explored the mechanisms of secondary propagation through surface contact on cold surfaces.A quantitative statistical experimental method was adopted to study the surface⁃contact transmission of micro⁃organisms,wherein the transfer rate of surface contact was the dependent variable and Escherichia coli was used as the indicator bacterium.The effects of contact pressure(0.44,0.86,1.55,2.25,and 2.94 N/cm^(2)),contact time(0,15,30,45,and 60 s),contact angle(15°and 25°),and surface materials(rubber and cotton gloves)were measured at two storage temperatures:cold storage(5℃)and freezing(-18℃).The results showed that as temperature decreases,the transfer of micro⁃organisms through surface contact becomes less probable.The contact time did not significantly influence the transfer rate of micro⁃organisms when items were handled at cold⁃storage temperatures.Based on these results,we recommend placing items as flat as possible to minimize the tilt angle when handling them at cold⁃storage temperatures.Additionally,if the tilt angle cannot be avoided,rubber gloves should be used when handling items stored at large tilt angles,whereas cotton gloves may be used for items placed at smaller angles. 展开更多
关键词 cold chain biological pollutant surface contact transfer rate transmission characteristics
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