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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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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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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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Latent and sensible heat fluxes in a very unstable atmospheric surface layer and weak-wind conditions in a tropical coastal ocean
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作者 Haitem M Almdhun Yusri Yusup +3 位作者 Ehsan Jolous Jamshidi Abdulghani Swesi Muhammad Fikri Sigid Abigail Adomako 《Atmospheric and Oceanic Science Letters》 2026年第1期47-52,共6页
The atmospheric surface layer of the tropical coastal ocean is commonly very unstable and experiences weakwind conditions.How the latent(LE)and sensible(H)heat fluxes behave under such conditions are unclear because o... The atmospheric surface layer of the tropical coastal ocean is commonly very unstable and experiences weakwind conditions.How the latent(LE)and sensible(H)heat fluxes behave under such conditions are unclear because of the lack of observation stations in the tropics.Thus,this study aims to analyze LE and H and the microclimate parameters influencing them.The authors deployed an eddy covariance system in a tropical coastal region for seven months.The microclimate parameters investigated were wind speed(U),vapor pressure deficit(Δe),temperature difference(ΔT),wind-vapor pressure deficit(UΔe),wind-temperature difference(UΔT),and atmospheric stability(z/L),where z is height and L is the Monin–Obukhov length.On the daily time scale,the results show that LE was more associated with U thanΔe,while H was more related toΔT than U.Cross-wavelet analysis revealed the strong coherence in the LE-U relationship for periods between one and two days,and for H–ΔT,0.5 to 1 day.Correlation and regression analyses confirmed the time series analyses results,where strong positive correlation coefficients(r)were obtained between LE and U(r=0.494)and H andΔT(r=0.365).Compared to other water bodies,the transfer coefficient of moisture(CE N)was found to be small(=0.40×10^(-3))and independent of stability;conversely,the transfer coefficient of heat(CH N)was closer to literature values(=1.00×10^(-3))and a function of stability. 展开更多
关键词 Latent heat Sensible heat Atmospheric surface layer Tropical coastal sea
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Droplets Self-Draining on the Horizontal Slippery Surface for Real-Time Anti-/De-Icing
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作者 Xiao Han Xu Sun +4 位作者 Di Zhao Mingjia Sun Kesong Liu Liping Heng Lei Jiang 《Nano-Micro Letters》 2026年第2期584-598,共15页
Undesired ice accumulation on infrastructure and transportation systems leads to catastrophic events and significant economic losses.Although various anti-icing surfaces with photothermal effects can initially prevent... Undesired ice accumulation on infrastructure and transportation systems leads to catastrophic events and significant economic losses.Although various anti-icing surfaces with photothermal effects can initially prevent icing,any thawy droplets remaining on the horizontal surface can quickly re-freezing once the light diminishes.To address these challenges,we have developed a self-draining slippery surface(SDSS)that enables the thawy droplets to self-remove on the horizontal surface,thereby facilitating real-time anti-icing with the aid of sunlight(100 m W cm^(-2)).This is achieved by sandwiching a thin pyroelectric layer between slippery surface and photothermal film.Due to the synergy between the photothermal and pyroelectric layers,the SDSS not only maintains a high surface temperature of 19.8±2.2℃at the low temperature(-20.0±1.0℃),but also generates amount of charge through thermoelectric coupling.Thus,as cold droplets dropped on the SDSS,electrostatic force pushes the droplets off the charged surface because of the charge transfer mechanism.Even if the surface freezes overnight,the ice can melt and drain off the SDSS within 10 min of exposure to sunlight at-20.0±1.0℃,leaving a clean surface.This work provides a new perspective on the anti-icing system in the real-world environments. 展开更多
关键词 Slippery surfaces Droplet self-draining Anti-/de-icing Thermoelectric coupling Charge transfer
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Surface flux–induced salinity change and its effects on ocean stratification in response to global warming
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作者 Hai Zhi Tianyi Ma +2 位作者 Rong-Hua Zhang Xiaokun Wang Minmin Wu 《Atmospheric and Oceanic Science Letters》 2026年第1期59-65,共7页
Global warming induced by increased CO_(2) has caused marked changes in the ocean.Previous estimates of ocean salinity change in response to global warming have considerable ambiguity,largely attributable to the diver... Global warming induced by increased CO_(2) has caused marked changes in the ocean.Previous estimates of ocean salinity change in response to global warming have considerable ambiguity,largely attributable to the diverse sensitivities of surface fluxes.This study utilizes data from the Flux-Anomaly-Forced Model Intercomparison Project to investigate how ocean salinity responds to perturbations of surface fluxes.The findings indicate the emergence of a sea surface salinity(SSS)dipole pattern predominantly in the North Atlantic and Pacific fresh pools,driven by surface flux perturbations.This results in an intensification of the“salty gets saltier and fresh gets fresher”SSS pattern across the global ocean.The spatial pattern amplification(PA)of SSS under global warming is estimated to be approximately 11.5%,with surface water flux perturbations being the most significant contributor to salinity PA,accounting for 8.1% of the change after 70 years in experiments since pre-industrial control(piControl).Notably,the zonal-depth distribution of salinity in the upper ocean exhibits lighter seawater above the denser water,with bowed isopycnals in the upper 400 m.This stable stratification inhibits vertical mixing of salinity and temperature.In response to the flux perturbations,there is a strong positive feedback due to consequent freshening.It is hypothesized that under global warming,an SSS amplification of 7.2%/℃ and a mixed-layer depth amplification of 12.5%/℃ will occur in the global ocean.It suggests that the salinity effect can exert a more stable ocean to hinder the downward transfer of heat,which provides positive feedback to future global warming. 展开更多
关键词 Sea surface salinity change Pattern amplification Upper-ocean stratification Flux-anomaly-forced model intercomparison project
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Mapping interaction between human activities and land surface temperature in the Yellow River Basin
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作者 ZHANG Zhongwu BAI Xue +4 位作者 LI Zhe YUE Xin ZHANG Xin YANG Shuo WANG Lu 《Journal of Geographical Sciences》 2026年第1期79-106,共28页
Human activities have significantly impacted the land surface temperature(LST),endangering human health;however,the relationship between these two factors has not been adequately quantified.This study comprehensively ... Human activities have significantly impacted the land surface temperature(LST),endangering human health;however,the relationship between these two factors has not been adequately quantified.This study comprehensively constructs a Human Activity Intensity(HAI)index and employs the Maximal Information Coefficient,four-quadrant model,and XGBoostSHAP model to investigate the spatiotemporal relationship and influencing factors of HAI-LST in the Yellow River Basin(YRB)from 2000 to 2020.The results indicated that from 2000 to 2020,as HAI and LST increased,the static HAI-LST relationship in the YRB showed a positive correlation that continued to strengthen.This dynamic relationship exhibited conflicting development,with the proportion of coordinated to conflicting regions shifting from 1:4 to 1:2,indicating a reduction in conflict intensity.Notably,only the degree of conflict in the source area decreased significantly,whereas it intensified in the upper and lower reaches.The key factors influencing the HAI-LST relationship include fractional vegetation cover,slope,precipitation,and evapotranspiration,along with region-specific factors such as PM_(2.5),biodiversity,and elevation.Based on these findings,region-specific ecological management strategies have been proposed to mitigate conflict-prone areas and alleviate thermal stress,thereby providing important guidance for promoting harmonious development between humans and nature. 展开更多
关键词 Yellow River Basin human activities land surface temperature maximal information coefficient XGBoost-SHAP
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Nitrogen and oxygen isotopes in nitrate and nitrite in the polluted surface waters from the Arno River Basin(Central Italy)
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作者 Lorenzo Chemeri Barbara Nisi +5 位作者 Andrea Pierozzi Jacopo Cabassi Marco Taussi Stefania Venturi Antonio Delgado Huertas Orlando Vaselli 《Journal of Environmental Sciences》 2026年第1期250-262,共13页
The Arno River Basin(Central Italy)is affected by a considerable anthropogenic pressure due to the presence of large cities and widespread industrial and agricultural practices.In this work,26 water samples from the A... The Arno River Basin(Central Italy)is affected by a considerable anthropogenic pressure due to the presence of large cities and widespread industrial and agricultural practices.In this work,26 water samples from the Arno River and its main tributaries were analyzed to assess the water pollution status.The geochemical composition of the Arno River changes from the source(dominated by a Ca-HCO_(3) facies)to the mouth(where a Na-Cl(SO4)chemistry prevails)with an increasing quality deterioration,as suggested by the Chemical Water Quality Index,due to anthropogenic contributions and seawater intrusion before flowing into the Ligurian Sea.The Ombrone and Usciana tributaries introduce anthropogenic pollutants into the Arno River,whilst Elsa tributary supplies significant contents of geogenic sulfate.The concentrations of dissolved nitrate and nitrite(up to 63 and 9 mg/L,respectively)and the respective isotopic values of𝛿15N and𝛿18O were also determined to understand origin and fate of the N-species in the Arno River Basin surface waters.The combined application of𝛿15N-NO_(3) and𝛿18O-NO_(3) and N-source apportionment modelling allowed the identification of soil organic nitrogen and sewage and domestic wastes as primary sources for dissolved NO_(3)-.The𝛿15N-NO_(2) and𝛿18O-NO_(2) values suggest that the nitrification process affects the ARB waters,thus controlling the abundances and proportion of the N-species.Our work indicates that additional efforts are needed to improve management strategies to reduce the release of nitrogenated species to the surface waters of the Arno River Basin,since little progress has been made from the early 2000s. 展开更多
关键词 River geochemistry Water pollution Nitrogen stable isotopes surface water management Water quality Anthropogenic pollution
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Ultra-fast and high-responsivity self-powered vis-NIR photodetector via surface charge transfer doping in MoTe_(2)/ReS_(2)heterostructures
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作者 Haozhe Ruan Yongkang Liu +5 位作者 Jianyu Wang Linjiang Xie Yixuan Wang Mengting Dong Zhangting Wu Liang Zheng 《Journal of Semiconductors》 2026年第1期99-106,共8页
The development of optoelectronic technologies demands photodetectors with miniaturization,broadband operation,high sensitivity,and low power consumption.Although 2D van der Waals(vd W)heterostructures are promising c... The development of optoelectronic technologies demands photodetectors with miniaturization,broadband operation,high sensitivity,and low power consumption.Although 2D van der Waals(vd W)heterostructures are promising candidates due to their built-in electric fields,ultrafast photocarrier separation,and tunable bandgaps,defect states limit their performance.Therefore,the modulation of the optoelectronic properties in such heterostructures is imperative.Surface charge transfer doping(SCTD)has emerged as a promising strategy for non-destructive modulation of electronic and optoelectronic characteristics in two-dimensional materials.In this work,we demonstrate the construction of high-performance p-i-n vertical heterojunction photodetectors through SCTD of MoTe_(2)/ReS_(2)heterostructure using p-type F_(4)-TCNQ.Systematic characterization reveals that the interfacial doping process effectively amplifies the built-in electric field,enhancing photogenerated carrier separation efficiency.Compared to the pristine heterojunction device,the doped photodetector exhibits remarkable visible to nearinfrared(635-1064 nm)performance.Particularly under 1064 nm illumination at zero bias,the device achieves a responsivity of 2.86 A/W and specific detectivity of 1.41×10^(12)Jones.Notably,the external quantum efficiency reaches an exceptional value of 334%compared to the initial 11.5%,while maintaining ultrafast response characteristics with rise/fall times of 11.6/15.6μs.This work provides new insights into interface engineering through molecular doping for developing high-performance vd W optoelectronic devices. 展开更多
关键词 MoTe_(2)/ReS_(2)heterostructure broadband photodetector surface charge transfer doping P-I-N
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Boosting the adsorption performance of ethanol on surface chemistry modified activated carbon fiber
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作者 Mengyan Wang Yuxuan Wang +6 位作者 Junhao Wang Yinghui Han Jianxiao Yang Suchan Yang Yuanxun Zhang Peng Huo Xin Zhang 《Journal of Environmental Sciences》 2026年第1期178-186,共9页
As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This stud... As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This study prepared surface polarity-modified ACF using the heteroatom doping method.The modified ACF possessed a richer array of strongly polar oxygen/nitrogen-containing functional groups(primarily phenolic hydroxyl and lactone groups),a larger specific surface are1,and a more developed micropore structure.The adsorption capacities of ethanol for O-ACF and N-ACF were 4.110 mmol/g and 1.698 mmol/g,respectively,which were 11.3 times and 4.7 times those of unmodified ACF.This was a significant improvement over our previous work(0.363 mmol/g).The improvement of adsorption capacity for the N-ACF was mainly due to the higher specific surface are1,greater number of micropores(more adsorption sites)and abundant existence of defects,whereas,for O-ACF,the improvement mainly relied on the abundant presence of oxygen-containing functional groups on the surface.However,water had a negative effect on the adsorption of ethanol for the modified ACF due to competitive adsorption and the disappearance of capillary condensation.It was further revealed that the adsorption process of ethanol and water was quite different.It obeyed the linear driving force(LDF)model for ethanol adsorption,however,the intraparticle diffusion(IPD)model for water adsorption. 展开更多
关键词 Activated carbon fiber(ACF) Heteroatom doping surface polarity-modified Polar functional groups Microporous filling Linear driving force(LDF) In-particle diffusion(IPD)
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Coexistence of near-E_(F) Van Hove Singularity and in-Gap Topological Dirac Surface States in Superconducting Electrides
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作者 Yin Yang Peihan Sun +9 位作者 Ye Shen Zhijun Tu Pengcheng Ma Hongrun Zhen Tianqi Wang Longli Tian Tian Cui Hechang Lei Kai Liu Zhonghao Liu 《Chinese Physics Letters》 2026年第1期213-217,共5页
Superconducting elect rides have attracted growing attention for their potential to achieve high superconducting transition temperatures(T_(C))under pressure.However,many known elect rides are chemically reactive and ... Superconducting elect rides have attracted growing attention for their potential to achieve high superconducting transition temperatures(T_(C))under pressure.However,many known elect rides are chemically reactive and unstable,making high-quality single-crystal growth,characterization,and measurements difficult,and most do not exhibit superconductivity at ambient pressure.In contrast,La_(3) In stands out for its ambient-pressure superconductivity(T_(C)∼9.4 K)and the availability of high-quality single crystals.Here,we investigate its low-energy electronic structure using angle-resolved photoemission spectroscopy and first-principles calculations.The bands near the Fermi energy(E_(F))are mainly derived from La 5d and In 5p orbitals.A saddle point is directly observed at the Brillouin zone(BZ)boundary,while a three-dimensional Van Hove singularity crosses E_(F) at the BZ corner.First-principles calculations further reveal topological Dirac surface states within the bulk energy gap above E_(F).The coexistence of a high density of states and in-gap topological surface states near𝐸F suggests that La3In offers a promising platform for tuning superconductivity and exploring possible topological superconducting phases through doping or external pressure. 展开更多
关键词 ambient pressure superconductivity superconducting elect rides gap topological Dirac surface states La superconducting electrides near e f Van Hove singularity angle resolved photoemission spectroscopy elect rides
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浅谈SMT课程“教室+车间”双向联动教学模式
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作者 王辉 《汽车维护与修理》 2025年第24期8-9,共2页
文章以表面贴装技术(SMT)课程为切入点,结合汽车维修专业特点,构建“教室+车间”双向联动的教学模式,通过重构课程内容、引入汽车电子真实项目、实施校企双导师制,并依托校内SMT实训平台与汽车维修车间联动运行,实现电子制造技术与汽车... 文章以表面贴装技术(SMT)课程为切入点,结合汽车维修专业特点,构建“教室+车间”双向联动的教学模式,通过重构课程内容、引入汽车电子真实项目、实施校企双导师制,并依托校内SMT实训平台与汽车维修车间联动运行,实现电子制造技术与汽车后市场服务的深度融合。实践表明,该教学模式显著提升了学生的综合技术能力、岗位适应性和职业素养,尤其在汽车电路板(PCB)维修、发动机控制模块故障诊断与再制造等方面展现出良好的应用成效,为培养“懂制造、会维修”的复合型技术技能人才提供了可推广的路径。 展开更多
关键词 产教融合 smt课程 教室+车间 教学模式
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基于工业互联网的SMT车间数字化解决方案 被引量:1
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作者 李晨阳 蔡冬 +3 位作者 张健 程毅辉 凌立 陶洁 《电子工艺技术》 2025年第4期60-63,共4页
数字化是现代智能制造的重要标签,也是生产效率和管理标准化提升的有效手段。基于工业互联网,针对某公司SMT车间的实际情况,阐述了一种包含了众多模块的数字化解决方案。该方案实现了SMT车间全流程可视化管理的同时,也可以辅助生产单位... 数字化是现代智能制造的重要标签,也是生产效率和管理标准化提升的有效手段。基于工业互联网,针对某公司SMT车间的实际情况,阐述了一种包含了众多模块的数字化解决方案。该方案实现了SMT车间全流程可视化管理的同时,也可以辅助生产单位及时获取生产执行进度,进行精益生产管理,有效管控产品品质。该方案通过过程管控、放错预警、辅助决策员工动作,可以有效提升生产效率,保证工厂高端精密制造的质量,助力设备管理提效,给企业带来较大经济收益。 展开更多
关键词 数字化 工业互联网 smt
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基于DOE方法的EBC连接器SMT不良缺陷分析 被引量:1
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作者 罗国军 王能松 +2 位作者 刘余林 罗旋 袁子良 《机电工程技术》 2025年第9期168-172,共5页
EBC连接器是5G板对板和板对模块的射频互连元件,通过SMT (Surface Mount Technology)工艺与PCB板焊接连通。由于EBC连接器在SMT之后,出现锡珠、空洞、位置偏移、爬锡高度不良等缺陷,影响天线的波频信号,甚至影响整个产品的可靠性。将介... EBC连接器是5G板对板和板对模块的射频互连元件,通过SMT (Surface Mount Technology)工艺与PCB板焊接连通。由于EBC连接器在SMT之后,出现锡珠、空洞、位置偏移、爬锡高度不良等缺陷,影响天线的波频信号,甚至影响整个产品的可靠性。将介绍基于DOE (Design of Experiments)方法,分析EBC连接器SMT工艺过程中,焊锡不良缺陷特征、规律,导致不良缺陷产生的可能原因;结合所有工序中,设备、工装夹具、物料、工艺参数,确定关键因子,排除非关键因子。通过Minitab软件,在DOE中创建因子,依据设计试验表序列,安排试验。采用响应曲面方法来分析响应变量“不良缺陷率”依赖于自变量因子,找到自变量因子的设置在望目0.5时,在响应曲面设计的响应优化器可得到,降低与解决SMT不良缺陷率最优试验区域:钢网开孔方式“梅花开孔”,锡粉型号TYPE3,回流曲线升温斜率1.166 7℃/s。基于DOE的接器SMT不良缺陷分析方法,可以系统地研究各种因素对不良缺陷的影响,找出关键因子并优化工艺条件。 展开更多
关键词 连接器 锡膏 钢网 smt 回流焊 DOE
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小型化SMT型X波段微带环行器的设计与验证 被引量:1
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作者 杨雷 陈江山 《遥测遥控》 2025年第4期60-66,共7页
为了满足雷达及通信系统小型化、宽带化、集成化、电磁兼容等需求,本文运用陶瓷嵌套工艺设计并制作了基于Mg系铁氧体材料的低损耗X波段的表贴式微带环行器。通过三维全电磁仿真(HFSS),设计了“鱼翅形”微带旋磁结,实现了器件的小型化与... 为了满足雷达及通信系统小型化、宽带化、集成化、电磁兼容等需求,本文运用陶瓷嵌套工艺设计并制作了基于Mg系铁氧体材料的低损耗X波段的表贴式微带环行器。通过三维全电磁仿真(HFSS),设计了“鱼翅形”微带旋磁结,实现了器件的小型化与宽带化。为实现表贴(SMT)封装,通过HFSS优化设计了陶瓷填充的金属化过孔结构,并采用高磁导率铁St12金属做屏蔽罩,确保环行器独立工作,与系统中其他元件互不干扰,同时实现电磁屏蔽和磁传导。最后根据优化设计结果进行器件制作和测试,测试结果表明:本文设计的SMT型环行器全封装尺寸达6 mm×6 mm×4 mm,在7 GHz~13 GHz(带宽达到60%)频段范围内,插损<0.8 dB,隔离度>18 dB,驻波比<1.30,性能良好,且适合大规模自动化贴装。 展开更多
关键词 铁氧体 微带 环行器 smt
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Influence of surface layer slurry temperature on surface cracks and holes of ZTC4 titanium alloy by investment casting 被引量:1
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作者 Wei-dong Li Xu-na Shi 《China Foundry》 2025年第1期90-98,共9页
In this work,the influences of surface layer slurry at different temperatures(10℃,14℃,18℃,22℃)on wax patterns deformation,shrinkage,slurry coating characteristics,and the surface quality of the casting were invest... In this work,the influences of surface layer slurry at different temperatures(10℃,14℃,18℃,22℃)on wax patterns deformation,shrinkage,slurry coating characteristics,and the surface quality of the casting were investigated by using a single factor variable method.The surface morphologies of the shell molds produced by different temperatures of the surface(first)layer slurries were observed via electron microscopy.Furthermore,the microscopic composition of these shell molds was obtained by EDS,and the osmotic effect of the slurry on the wax patterns at different temperatures was also assessed by the PZ-200 Contact Angle detector.The forming reasons for the surface cracks and holes of thick and large ZTC4 titanium alloy by investment casting were analyzed.The experimental results show that the surface of the shell molds prepared by the surface layer slurry with a low temperature exhibits noticeable damage,which is mainly due to the poor coating performance and the serious expansion and contraction of wax pattern at low temperatures.The second layer shell material(SiO_(2),Al_(2)O_(3))immerses into the crack area of the surface layer,contacts and reacts with the molten titanium to form surface cracks and holes in the castings.With the increase of the temperature of surface layer slurry,the damage to the shell surface tends to weaken,and the composition of the shell molds'surface becomes more uniform with less impurities.The results show that the surface layer slurry at 22℃is evenly coated on the surface of the wax patterns with appropriate thickness,and there is no surface shell mold rupture caused by sliding slurry after sand leaching.The surface layer slurry temperature is consistent with the wax pattern temperature and the workshop temperature,so there is no damage of the surface layer shell caused by expansion and contraction.Therefore,the shell mold prepared by the surface layer slurry at this temperature has good integrity,isolating the contact between the low inert shell material and the titanium liquid effectively,and the ZTC4 titanium alloy cylinder casting prepared by this shell mold is smooth,without cracks and holes. 展开更多
关键词 titanium alloy surface layer slurry surface cracks surface holes investment casting
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Advances in magnesium-based bioresorbable cardiovascular stents: Surface engineering and clinical prospects 被引量:2
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作者 Ganesh Kumar Subham Preetam +5 位作者 Arunima Pandey Nick Birbilis Saad Al-Saadi Pooria Pasbakhsh Mikhail Zheludkevich Poovarasi Balan 《Journal of Magnesium and Alloys》 2025年第3期948-981,共34页
Magnesium(Mg)-based bioresorbable stents represent a potentially groundbreaking advancement in cardiovascular therapy;offering tem-porary vessel support and complete biodegradability—addressing limitations of traditi... Magnesium(Mg)-based bioresorbable stents represent a potentially groundbreaking advancement in cardiovascular therapy;offering tem-porary vessel support and complete biodegradability—addressing limitations of traditional stents like in-stent restenosis and long-term com-plications.However,challenges such as rapid corrosion and suboptimal endothelialisation have hindered their clinical adoption.This review highlights the latest breakthroughs in surface modification,alloying,and coating strategies to enhance the mechanical integrity,corrosion resistance,and biocompatibility of Mg-based stents.Key surface engineering techniques,including polymer and bioactive coatings,are ex-amined for their role in promoting endothelial healing and minimising inflammatory responses.Future directions are proposed,focusing on personalised stent designs to optimize efficacy and long-term outcomes,positioning Mg-based stents as a transformative solution in interventional cardiology. 展开更多
关键词 Magnesium alloy Cardiovascular stent surface modification Corrosion BIOCOMPATIBILITY Biomedical application
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Research on the Hydrophobic Performance of Bamboo Surface Treated via Coordinated Plasma and PDMS Solution Treatments 被引量:1
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作者 Zihan Ma Yan Wu +2 位作者 Hongyan Wang Shaofei Yuan Jian Zhang 《Journal of Renewable Materials》 2025年第5期931-955,共25页
Herein,the surface of Moso bamboo was hydrophobically modified by combining O_(2)/N_(2)plasma treatments with polydimethylsiloxane(PDMS)solution treatment as the hydrophobic solution.The effects of plasma treatment pr... Herein,the surface of Moso bamboo was hydrophobically modified by combining O_(2)/N_(2)plasma treatments with polydimethylsiloxane(PDMS)solution treatment as the hydrophobic solution.The effects of plasma treatment process(power and time),PDMS solution concentration,and maceration time on the hydrophobic performance of bamboo specimens were studied,and the optimal treatment conditions for improving the hydrophobicity were determined.Scanning electron microscopy(SEM),fourier transform infrared(FTIR),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS)were used to analyze the surface morphology,chemical structure,and functional groups in the specimens before and after the plasma and PDMS solution treatments under optimal conditions.Response surface analysis was also performed to determine the optimal treatment conditions.Results show that the hydrophobic performance of the Moso bamboo surface is effectively improved and the surface energy is reduced after the coordinated treatment.The optimal conditions for improving the hydrophobic performance of Moso bamboo surface are a treatment power of 800 W,treatment time of 15 s,O_(2)flow rate of 1.5 L/min,PDMS solution concentration of 5%,and maceration time of 60 min for O_(2)plasma treatment and a treatment power of 1000 W,treatment time of 15 s,N_(2)flow rate of 1.5 L/min,PDMS solution concentration of 5%,and maceration time of 60 min for N_(2)plasma treatment.After treatment,silicone oil particles and plasma etching traces are observed on the bamboo surface.Moreover,Si-O bonds in the PDMS solution are grafted to the bamboo surface via covalent bonds,thereby increasing the contact angle and decreasing the surface energy to achieve the hydrophobic effect. 展开更多
关键词 Moso bamboo PDMS MODIFICATION surface hydrophobicity
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Recent advancements in the design of micro/nanostructured superhydrophobic surfaces on magnesium alloys 被引量:1
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作者 Sihui Ouyang Fengyi Wang +4 位作者 Jia She Liying Qiao Ao Fu Xianhua Chen Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第2期457-485,共29页
As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in ... As one of the lightest engineering materials,magnesium(Mg)alloy possesses excellent mechanical performance,meeting the needs of versatile engineering fields and holding the potential to address cutting-edge issues in aerospace,electronics,biomedicine.The design of superhydrophobic(SHB)surfaces with micro and nanostructures can endow Mg alloys with multiple functionalities,such as self-cleaning,self-healing,antibacterial,and corrosion resistance.Over the past decade,researchers have drawn inspiration from nature to implement biomimetic design principles,resulting in the rapid development of micro/nanostructured SHB surfaces on Mg alloys,which hold great promise for biomedical applications.This review comprehensively introduces the biomimetic design principles of micro/nanostructured SHB surfaces on Mg alloys,discusses the challenges along with advantages and disadvantages of current preparation methods,and explores the future perspectives for preparing these SHB surfaces,providing strategies to enhance their performance in biomedical applications. 展开更多
关键词 Magnesium alloy Biomimetic design Superhydrophobic surface Biomedical application.
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