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Comparison of tear film quantity parameters between keratoconus and normal eyes
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作者 Foroozan Narooie-Noori Masoud Khorrami-Nejad +1 位作者 Nabaa Ayad Hesam Hashemian 《International Journal of Ophthalmology(English edition)》 2026年第1期42-47,共6页
AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including pati... AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including patients with KCN and age-matched healthy individuals with normal corneas,were recruited from those referred to Farabi Eye Hospital,Iran,in 2023.To better account for genetic and environmental factors,the control group comprised healthy individuals who were relatives of KCN patients and had normal corneal topography.Tear quantity parameters were evaluated in the following order:NITBUT,TBUT,and Schirmer tests.RESULTS:The mean age of cases in KCN(61.7%males)and normal(63.5%males)participants was 27.54±5.44y(range 19 to 38)and 27.52±5.63y(range 20 to 38),respectively(P=0.976).NIBUT,TBUT,and Schirmer’s tests were significantly lower in KCN group compared to normal controls(all P<0.001).The mean difference for NIBUT was-7.81s(P<0.001),and for TBUT was-7.61s(P<0.001).Schirmer test values were also significantly lower in the KCN group,with a mean difference of-5.61 mm compared to normal people(P<0.001).CONCLUSION:Our findings demonstrate significant tear film impairment in KCN.The reductions in NIBUT,TBUT and Schirmer scores highlight an underlying tear film dysfunction in KCN that extends beyond the morphological changes of the cornea. 展开更多
关键词 KERATOCONUS tear breakup time noninvasive tear breakup time Schirmer test tear film
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Correction: Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics: A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期608-608,共1页
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th... Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected. 展开更多
关键词 charge carrier behavior exciton behavior comprehensive review thick film organic photovoltaics nano micro letters
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Ultrahigh Dielectric Permittivity of a Micron-Sized Hf_(0.5)Zr_(0.5)O_(2) Thin-Film Capacitor After Missing of a Mixed Tetragonal Phase
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作者 Wen Di Zhang Bing Li +3 位作者 Wei Wei Wang Xing Ya Wang Yan Cheng An Quan Jiang 《Nano-Micro Letters》 2026年第1期144-153,共10页
Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received wides... Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received widespread applications in high-storage-density dynamic random access memory and energy-efficient complementary metal-oxide-semiconductor devices.During bipolar high electric-field cycling in numbers close to dielectric breakdown,the dielectric permittivity suddenly increases by 30 times after oxygen-vacancy ordering and ferroelectric-to-nonferroelectric phase transition of near-edge plasma-treated Hf_(0.5)Zr_(0.5)O_(2) thin-film capacitors.Here we report a much higher dielectric permittivity of 1466 during downscaling of the capacitor into the diameter of 3.85μm when the ferroelectricity suddenly disappears without high-field cycling.The stored charge density is as high as 183μC cm^(−2) at an operating voltage/time of 1.2 V/50 ns at cycle numbers of more than 10^(12) without inducing dielectric breakdown.The study of synchrotron X-ray micro-diffraction patterns show missing of a mixed tetragonal phase.The image of electron energy loss spectroscopy shows the preferred oxygen-vacancy accumulation at the regions near top/bottom electrodes as well as grain boundaries.The ultrahigh dielectric-permittivity material enables high-density integration of extremely scaled logic and memory devices in the future. 展开更多
关键词 Hf_(0.5)Zr_(0.5)O_(2)thin film Ultrahigh dielectric permittivity Near-edge plasma treatment Oxygen vacancy Charge storage
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Robust ferroelectricity in ultrathin BaTiO_(3)films deposited at room temperature
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作者 Cong-Meng Li Hui Li +2 位作者 Jian Chen Ming-Kai Li Hong-Wei Gu 《Rare Metals》 2025年第7期5106-5111,共6页
Ferroelectric materials are widely applied in the ferroelectronic devices,photovoltaics,and so on.Ultrathin ferroelectric thin films are highly desired for their applications,which still remain a challenge.In this wor... Ferroelectric materials are widely applied in the ferroelectronic devices,photovoltaics,and so on.Ultrathin ferroelectric thin films are highly desired for their applications,which still remain a challenge.In this work,the ultrathin barium titanate(BaTiO_(3),BTO)films are deposited directly on the fluorine-doped tin oxide glass(SnO_(2):F,FTO)substrates by radio frequency magnetron sputtering method at different temperatures.All BTO ultrathin films exhibit strong ferroelectric properties.Interestingly,BTO thin films deposited at room temperature(RT)also exhibit robust ferroelectricity.The polar domains are switched reversibly with a phase degree of~180°by piezoelectric force microscopy for the BTO thin films deposited at room temperature,attributing to the strain and ion migration. 展开更多
关键词 radio frequency magnetron sputtering method barium titanate batio bto films ferroelectronic devicesphotovoltaicsand ferroelectric propertiesinterestinglybto ferroelectric materials ultrathin films ferroelectric thin films barium titanate
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Arrangement guideline of film holes along conjugate temperature difference in turbine guide vanes
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作者 Yuhao JIA Yongbao LIU +2 位作者 Xing HE Zewei MENG Shuai ZHAO 《Chinese Journal of Aeronautics》 2025年第6期242-259,共18页
A film hole arrangement guideline along the temperature difference is proposed.The performance of different film holes arrangement and the impact of parameters are investigated though cascade wind tunnel test and nume... A film hole arrangement guideline along the temperature difference is proposed.The performance of different film holes arrangement and the impact of parameters are investigated though cascade wind tunnel test and numerical simulations.Finally,the optimized flow field structure and the mechanism of its effects are explored.Under the same operating conditions,Hole pattern#2(arrangement along the 50 K temperature difference line)can reduce coolant consumption by half while achieves the same cooling effect as original film hole arrangement.Additionally,Hole pattern#2 reduces the temperature difference between the suction and pressure sides of the vane,effectively protecting the structural strength.At mass flow ratio is 6.23%,Hole pattern#2 achieves both good cooling effectiveness and relatively saves coolant consumption,offering the highest costeffectiveness.The modulation in the position of film holes results in different local pressures affecting the flow inside the cooling chamber.The coupling of internal and external flows leads to different vortex structures near the outlet of the film holes,thereby influencing the film effectiveness.Hole pattern#2 does not exhibit significant high-cooling regions,but it shows a more uniform distribution of overall cooling effectiveness.Therefore,optimizing the arrangement of film holes and spacing them along the temperature difference is considered a crucial technical means to enhance the efficiency of gas turbines. 展开更多
关键词 film cooling Turbineguidevane film hole layout Temperaturedifference CASCADE Wind tunnel experiment
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Solution for Environmentally Friendly Silver Surface Magnetron Sputtering Color Titanium Film Layer Technology
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作者 Huan Zhu Krisada Daoruang Chalisa Apiwathnasorn 《Journal of Environmental & Earth Sciences》 2025年第1期562-572,共11页
Silver is an elegant white precious metal,but it is easily oxidized by O3,SO2,and H2S in the air,turning yellow or dark,which affects its decorative effect.The existing silver coating,primarily prepared through the el... Silver is an elegant white precious metal,but it is easily oxidized by O3,SO2,and H2S in the air,turning yellow or dark,which affects its decorative effect.The existing silver coating,primarily prepared through the electroplating process,poses serious environmental pollution problems.It is necessary to seek new,green,and environmentally friendly coating processes while also enhancing the color palette of silver jewelry coatings.Titanium film layers were deposited on Ag925 and Ag999 surfaces using magnetron sputtering coating technology.The effects of sputtering time,substrate surface state,reaction gas type and time,and film thickness on the color of the film layers were studied,and the anti discoloration performance of the obtained film layers under the optimal process was tested.The experimental results show that when the sputtering time varies from 5 to 10 minutes,injecting argon,oxygen,and nitrogen into the coating chamber yields rich colors such as purple with a red tint,blue,yellow green,yellowish purple,and blue purple.The precise control of gas injection time has a significant impact on the color of the film layer.In terms of anti tarnish performance,the film showed good stability in the artificial sweat immersion test.From an environmental perspective,the magnetron sputtering titanium film process has no harmful gas or liquid emissions,which aligns with the sustainable development trend of the jewelry industry and holds great promise for application.This study has improved the visual effect and practical performance of the product,providing important theoretical basis and experimental data support for the application of environmentally friendly silver surface vacuum magnetron sputtering titanium thin film coating technology. 展开更多
关键词 Environmental Protection Magnetron Sputtering SILVER Colored film Titanium film Layer
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Enhancement of Ising Superconductivity in Pb_(1-x)Bi_(x) Ultrathin Films
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作者 Yitong Gu Kun Xie +9 位作者 Yingcai Qian Yuzhou Liu Siyu Huo Yumin Xia Desheng Cai Wenhui Pang Gan Yu Haoen Chi Chuanying Xi Shengyong Qin 《Chinese Physics Letters》 2025年第5期176-187,共12页
Ising superconductivity has garnered much attention in recent years due to its extremely high in-plane upper critical field (B_(c2)).Here,we fabricated 14 multilayer Pb_(1-x)Bi_(x) (0%≤x≤40%) thin films on Si (111)-... Ising superconductivity has garnered much attention in recent years due to its extremely high in-plane upper critical field (B_(c2)).Here,we fabricated 14 multilayer Pb_(1-x)Bi_(x) (0%≤x≤40%) thin films on Si (111)-7×7 reconstructed surface by molecular beam epitaxy.Large B_(c2) beyond the Pauli limit is observed in all the Pb_(1-x)Bi_(x) films,indicating that they may exhibit characteristics of Ising superconductivity.Moreover,the introduction of Bi doping can significantly enhance and effectively tune the in-plane B_(c2) of Pb_(1-x)Bi_(x) films,which will help us better understand Ising superconductivity and provide a new platform for the development of tunable Ising superconductors. 展开更多
关键词 plane upper critical field molecular beam epitaxylarge ising superconductivitymoreoverthe ising superconductivity ultrathin films Pb xBix bi doping thin films
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The Effect of Carrier Doping and Thickness on the Electronic Structures of La_(3)Ni_(2)O_(7)Thin Films
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作者 Haoliang Shi Zihao Huo +4 位作者 Guanlin Li Hao Ma Tian Cui Daoxin Yao Defang Duan 《Chinese Physics Letters》 2025年第8期201-229,共29页
The discovery of high-temperature superconductivity in bilayer nickelate La_(3)Ni_(2)O_(7)under high-pressure conditions has spurred extensive efforts to stabilize superconductivity at ambient pressure.Recently,the re... The discovery of high-temperature superconductivity in bilayer nickelate La_(3)Ni_(2)O_(7)under high-pressure conditions has spurred extensive efforts to stabilize superconductivity at ambient pressure.Recently,the realization of superconductivity in compressively strained La_(3)Ni_(2)O_(7)thin films grown on the SrLaAlO_(4)substrates,with a T_(c)exceeding 40 K,represents a significant step toward this goal.Here,we investigate the influence of film thickness and carrier doping on the electronic structure of La_(3)Ni_(2)O_(7)thin films,ranging from 0.5 to 3 unit cells,using first-principles calculations.For a 2 unit-cell film with an optimal doping concentration of 0.3 hole per formula unit(0.15 hole/Ni),the Ni-d_(z^(2))interlayer bonding state crosses the Fermi level,resulting in the formation ofγpockets at the Fermi surface.These findings align with angle-resolved photoemission spectroscopy experimental data.Our results provide theoretical validation for the recent experimental discovery of ambient-pressure superconductivity in La_(3)Ni_(2)O_(7)thin films and underscore the significant impact of film thickness and carrier doping on electronic property modulation. 展开更多
关键词 bilayer nickelate film thickness electronic structure l electronic structure la ni o thin films carrier doping stabilize superconductivity SUPERCONDUCTIVITY
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Enhancing carbon sequestration and greenhouse gas mitigation in semiarid farmland:The promising role of biochar application with biodegradable film mulching 被引量:2
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作者 Jinwen Pang Zhonghong Tian +9 位作者 Mengjie Zhang Yuhao Wang Tianxiang Qi Qilin Zhang Enke Liu Weijun Zhang Xiaolong Ren Zhikuan Jia Kadambot H.M.Siddique Peng Zhang 《Journal of Integrative Agriculture》 2025年第2期517-535,共19页
Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising... Long-term mulching has improved crop yields and farmland productivity in semiarid areas,but it has also increased greenhouse gas(GHG)emissions and depleted soil fertility.Biochar application has emerged as a promising solution for addressing these issues.In this study,we investigated the effects of four biochar application rates(no biochar(N)=0 t ha^(-1),low(L)=3 t ha^(-1),medium(M)=6 t ha^(-1),and high(H)=9 t ha^(-1))under film mulching and no mulching conditions over three growing seasons.We assessed the impacts on GHG emissions,soil organic carbon sequestration(SOCS),and maize yield to evaluate the productivity and sustainability of farmland ecosystems.Our results demonstrated that mulching increased maize yield(18.68-41.80%),total fixed C in straw(23.64%),grain(28.87%),and root(46.31%)biomass,and GHG emissions(CO_(2),10.78%;N_(2)O,3.41%),while reducing SOCS(6.57%)and GHG intensity(GHGI;13.61%).Under mulching,biochar application significantly increased maize yield(10.20%),total fixed C in straw(17.97%),grain(17.69%)and root(16.75%)biomass,and SOCS(4.78%).Moreover,it reduced the GHG emissions(CO_(2),3.09%;N_(2)O,6.36%)and GHGI(12.28%).These effects correlated with the biochar addition rate,with the optimal rate being 9.0 t ha^(-1).In conclusion,biochar application reduces CO_(2) and N_(2)O emissions,enhances CH_(4) absorption,and improves maize yield under film mulching.It also improves the soil carbon fixation capacity while mitigating the warming potential,making it a promising sustainable management method for mulched farmland in semiarid areas. 展开更多
关键词 BIOCHAR film mulching greenhouse gas emissions carbon sequestration
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Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau 被引量:2
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作者 Xiaoqing Han Pengfei Dang +12 位作者 Lechen Liao Fangqi Song Miaomiao Zhang Maoxue Zhang Guoqing Li Shuyue Wen Ning Yang Xiping Pan Xiaofan Wang WenWang Xiaoliang Qin Charles O.Joseph Kadambot H.M.Siddique 《Journal of Environmental Sciences》 2025年第1期359-369,共11页
Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulc... Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application. 展开更多
关键词 Plastic film mulching Slow-release fertilizer Maize grain yield Carbon footprint Economic benefits
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Film thickness effect on 2D lead-free hybrid double perovskite properties: Band gap, photocurrent and stability 被引量:1
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作者 Mohamed Saber Lassoued Faizan Ahmad Yanzhen Zheng 《Chinese Chemical Letters》 2025年第4期449-454,共6页
Lead-free hybrid double perovskites(LFHDPs) have received a lot of attention due to their environmental friendliness and promising attributes. However, studying the effect of film thickness on LFHDPs optoelectronic pr... Lead-free hybrid double perovskites(LFHDPs) have received a lot of attention due to their environmental friendliness and promising attributes. However, studying the effect of film thickness on LFHDPs optoelectronic properties has not yet been investigated. Herein, we synthesized two new Ruddlesden–Popper LFHDPs, namely(C_(5)H_(12)N)_(4)AgBiI_(8)(CAB-1) and(C_(6)H_(14)N)_(4)Ag Bi I8(CAB-2) using cyclopentylamine and cyclohexylamine as monoamine ligands. Indeed, these two Ag(Ⅰ)-Bi(Ⅲ) LFHDPs form smooth and uniform films ranging in thickness from 250 nm to 1 μm, with preferred orientations. Notably, the studies on the optical properties showed that the direct band gap value decreased from 2.17 e V to 1.91 e V for CAB-1 and from 2.05 e V to 1.86 e V for CAB-2 with increasing thickness. Accordingly, photo-current response using a xenon lamp revealed a significant difference of over 1000 n A between light and dark conditions for1 μm-thickness films, suggesting potential for light harvesting. Other than that, thicker films of CAB-1and CAB-2 exhibit high stability for 90 days in a relatively humid environment(RH of 55%), paving the way for promising optoelectronic applications. 展开更多
关键词 LEAD-FREE Double perovskites film thickness Photocurrent response High stability
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New strategy for Mg-air battery voltage-efficiency synergy by engineering protective film with cation vacancies on Mg anode surface 被引量:1
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作者 Yuying He Qianyu Wang +6 位作者 Jinghuai Zhang Lele Wang Shujuan Liu Zehua Li Zhen Wei Hao Dong Xiaobo Zhang 《Journal of Materials Science & Technology》 2025年第10期24-41,共18页
Although the Mg-air battery with high theoretical energy density is desirable for the energy supply of marine engineering equipment,its applications remain limited due to the low actual discharge voltage and inferior ... Although the Mg-air battery with high theoretical energy density is desirable for the energy supply of marine engineering equipment,its applications remain limited due to the low actual discharge voltage and inferior Mg anode utilization rate.In addition to the microstructure of Mg alloy anodes,the properties of discharge product films are of great importance to the discharge performance.Herein,the discharge behaviors of Mg-Y-Zn alloys are first studied mainly from the perspective of film properties.Through contrastive analysis,it is found that the sufficient Y^(3+) produced during the discharge process can substitute Mg^(2+) in Mg(OH)_(2) to introduce effective cation vacancies.The Mg-Y-Zn anode with profuse cation vacancies in the product film shows a synergy of potential and efficiency,and this can be attributed to an increase in the migration pathway for Mg^(2+),reducing the diffusion over-potential caused by the protective product film.This study is expected to provide a new strategy from the perspective of cation vacancy design of discharge film for developing high-performance Mg-air batteries. 展开更多
关键词 Mg alloy Mg-air battery Product film Cation vacancy Discharge performance
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Recent advances on the oxide film of ignition-proof magnesium alloys:A review 被引量:1
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作者 Jiaxuan Han Bo Hu +5 位作者 Zhenfei Jiang Fanjin Yao Zixin Li Dejiang Li Xiaoqin Zeng Wenjiang Ding 《Journal of Magnesium and Alloys》 2025年第1期4-29,共26页
Magnesium and its alloys offer lightweight advantage and have extensive development prospects,particularly in aerospace.However,their flammability poses a significant barrier on the development of Mg alloys.The igniti... Magnesium and its alloys offer lightweight advantage and have extensive development prospects,particularly in aerospace.However,their flammability poses a significant barrier on the development of Mg alloys.The ignition resistance of these alloys often depends on the protectiveness of the oxide film formed on the surface.This paper elucidates the formation mechanism of oxide film from thermodynamics and kinetics,classifying oxide films based on their layered structure to assess their protective properties.Furthermore,it comprehensively reviews the impact of characteristics on the protective effectiveness such as compactness,continuity,thickness,and mechanical properties.The paper also introduces various characterization methods for the microstructure and properties of oxide film.The primary objective of this paper is to enhance the comprehension of oxide film concerning the ignition resistance of Mg alloys and to furnish references for future advancements and research in Mg alloys with heightened ignition resistance. 展开更多
关键词 Magnesium alloys Ignition resistance Oxide film Layered structure Characterization methods
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Achieving ultrahigh anodic-efficiency and energy-density Mg–air battery via the discharge product film design of bulk Mg anode 被引量:1
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作者 Jialuo Huang Zuxiang Sun +4 位作者 Jianxin Tan Can Sun Xingpeng Liao Tao Ying Fuyong Cao 《Journal of Magnesium and Alloys》 2025年第6期2565-2580,共16页
This study exhibits a design of the discharge product film of a bulk AZ63-Ce-La-Ca(AZ63X)anode for Mg-air battery.An ideal discharge product film for Mg anode is that it could inhibit the anodic hydrogen evolution but... This study exhibits a design of the discharge product film of a bulk AZ63-Ce-La-Ca(AZ63X)anode for Mg-air battery.An ideal discharge product film for Mg anode is that it could inhibit the anodic hydrogen evolution but does not hinder the transfer of the electrons at the interface.Fortunately,the addition of Ce,La,and Ca into AZ63 alloy achieves this goal.The Mg-air battery with AZ63X anode in 3.5%Na Cl has an ultrahigh anodic efficiency of 85.7±1.7%and energy-density of 2431±53 mWh g^(-1)with the unique discharge product film,surpassing the values of most reported Mg-air batteries.Furthermore,the alloying elements reduce the anode delamination effect significantly by transforming the block Mg_(17)Al_(12)phase into the connected Mg_(17)Al_(12)structure and fine rod Al_(2)RE and Al_(2)Ca. 展开更多
关键词 Mg-air battery Discharge product film ANODE Discharge performance Hydrogen evolution
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Mechanism of the Fluidelastic Instability of a Flexible Tube with a Squeeze Film Within a Rigid Tube Array Subjected to Two-Phase Flow 被引量:1
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作者 YANG Shi-hao LAI Jiang ZHU Hong-jun 《China Ocean Engineering》 2025年第5期855-865,共11页
The influence of the squeeze film between the tube and the support structure on flow-induced vibrations is a critical factor in tube bundles subjected to two-phase cross-flow.This aspect can significantly alter the th... The influence of the squeeze film between the tube and the support structure on flow-induced vibrations is a critical factor in tube bundles subjected to two-phase cross-flow.This aspect can significantly alter the threshold for fluidelastic instability and affect heat transfer efficiency.This paper presents a mathematical model incorporating the squeeze film force between the tube and the support structure.We aim to clarify the mechanisms underlying fluidelastic instability in tube bundle systems exposed to two-phase flow.Using a self-developed computer program,we performed numerical calculations to examine the influence of the squeeze film on the threshold of fluidelastic instability in the tube bundle system.Furthermore,we analyzed how the thickness and length of the squeeze film affect both the underlying mechanisms and the critical velocity of fluidelastic instability. 展开更多
关键词 fluidelastic instability tube bundles squeeze film eigenvalue problem two-phase flow
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Investigation of the formation processes of CO_(2) hydrate films on the interface of liquid carbon dioxide with humic acids solutions 被引量:1
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作者 Aleksey K.Sagidullin Sergey S.Skiba +1 位作者 Tatyana P.Adamova Andrey Y.Manakov 《Chinese Journal of Chemical Engineering》 2025年第3期53-61,共9页
Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the inte... Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle. 展开更多
关键词 HYDRATES Carbon dioxide Humic acids solutions Reaction kinetics Liquid liquid reaction film growth
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Poly(lactic acid)/Poly(butylene adipate-co-terephthalate)films with simultaneous high oxygen barrier and fast degradation properties
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作者 Mengjing Yang Yuxi Mao +4 位作者 Penghui Zhang Jie Li Zeming Tong Zhenguo Liu Yanhui Chen 《Green Energy & Environment》 SCIE EI CAS 2025年第1期1-10,共10页
Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are stil... Although poly(lactic acid)(PLA)is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films,the barrier properties of PLA films are still insufficient for high-barrier packaging applications.In this study,oxygen scavenger hydroxyl-terminated polybutadiene(HTPB)and cobalt salt catalyst were incorporated into the PLA/poly(butylene adipate-co-terephthalate)(PLA/PBAT),followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite films.The oxygen permeability coefficient of the composite film combined with 6 wt%oxygen scavenger and 0.4 wt%catalyst was decreased significantly from 377.00 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1) to 0.98 cc·mil·m^(-2)·day^(-1)·0.1 MPa^(-1),showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite film.Meanwhile,the degradation behavior of the composite film was also accelerated,exhibiting a mass loss of nearly 60%of the original mass after seven days of degradation in an alkaline environment,whereas PLA/PBAT composite film only showed a mass loss of 32%.This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior,which has great potential for high-demanding green chemistry packaging industries,including food,agricultural,and military packaging. 展开更多
关键词 Barrier property Oxygen scavenging Blow molding Eco-packaging Degradable composite film
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A review of graphene assembled films as platforms for electrochemical reactions
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作者 ZHU Yong-fang JI Xiao-dong +4 位作者 PAN Wen-kai WU Geng LI Peng LIU Bo HE Da-ping 《新型炭材料(中英文)》 北大核心 2025年第3期519-539,共21页
Because of their low electrical conductivity,sluggish ion diffusion,and poor stability,conventional electrode materials are not able to meet the growing demands of energy storage and portable devices.Graphene assemble... Because of their low electrical conductivity,sluggish ion diffusion,and poor stability,conventional electrode materials are not able to meet the growing demands of energy storage and portable devices.Graphene assembled films(GAFs)formed from graphene nanosheets have an ultrahigh conductivity,a unique 2D network structure,and exceptional mechanical strength,which give them the potential to solve these problems.However,a systematic understanding of GAFs as an advanced electrode material is lacking.This review focuses on the use of GAFs in electrochemistry,providing a comprehensive analysis of their synthesis methods,surface/structural characteristics,and physical properties,and thus understand their structure-property relationships.Their advantages in batteries,supercapacitors,and electrochemical sensors are systematically evaluated,with an emphasis on their excellent electrical conductivity,ion transport kinetics,and interfacial stability.The existing problems in these devices,such as chemical inertness and mechanical brittleness,are discussed and potential solutions are proposed,including defect engineering and hybrid structures.This review should deepen our mechanistic understanding of the use of GAFs in electrochemical systems and provide actionable strategies for developing stable,high-performance electrode materials. 展开更多
关键词 Graphene assembled films BATTERIES SUPERCAPACITORS Electrochemical sensors Synthesis methods
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Effect of Modified Mesoporous Silica Nanoparticle/Zein Composite Film on the Preservation of Fish Fillets
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作者 YIN Tianxiang JIANG Xinyue +2 位作者 SUN Tianyu LIU Xiaoli LIU Jinyuan 《食品科学》 北大核心 2025年第24期263-274,共12页
To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid... To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid(CA)within the zein matrix(EG/CA-MSN/Zein)was developed.This study compared the effects of EG/CA-MSN/Zein,polyethylene(PE),and zein films on the quality of fish fillets during refrigerated storage.The results showed that the EG/CA-MSN/Zein film significantly retarded the increase in pH and microbial growth.Moreover,the film had higher water-holding capacity(WHC),better texture,and color stability,as indicated by low-field nuclear magnetic resonance(LF-NMR),magnetic resonance imaging(MRI),and sensory evaluation.The EG/CA-MSN/Zein composite film extended the shelf life of crucian carp fillets by 3-4 days,highlighting its potential as an environmentally friendly and efficient packaging material for aquatic products. 展开更多
关键词 ZEIN composite film EUGENOL mesoporous silica nanoparticles food preservation
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Effect of Magnetron Sputtered Gas on Microstructure and Hydrogen Adsorption Performance of ZrCoRE Films
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作者 Zhou Chao Ma Zhanji +2 位作者 Li Gang Yang Lamaocao Zhang Huzhong 《稀有金属材料与工程》 北大核心 2025年第6期1451-1456,共6页
ZrCoRE(RE denotes rare earth elements)non-evaporable getter films have significant applications in vacuum packaging of micro-electro mechanical system devices because of their excellent gas adsorption performance,low ... ZrCoRE(RE denotes rare earth elements)non-evaporable getter films have significant applications in vacuum packaging of micro-electro mechanical system devices because of their excellent gas adsorption performance,low activation temperature and environmental friendliness.The films were deposited using DC magnetron sputtering with argon and krypton gases under various deposition pressures.The effects of sputtering gas type and pressure on the morphology and hydrogen adsorption performance of ZrCoRE films were investigated.Results show that the films prepared in Ar exhibit a relatively dense structure with fewer grain boundaries.The increase in Ar pressure results in more grain boundaries and gap structures in the films.In contrast,films deposited in Kr display a higher density of grain boundaries and cluster structures,and the films have an obvious columnar crystal structure,with numerous interfaces and gaps distributed between the columnar structures,providing more paths for gas diffusion.As Kr pressure increases,the film demonstrates more pronounced continuous columnar structure growth,accompanied by deeper and wider grain boundaries.This structural configuration provides a larger specific surface area,which significantly improves the hydrogen adsorption speed and capacity.Consequently,high Ar and Kr pressures are beneficial to improve the adsorption performance. 展开更多
关键词 NEG film magnetron sputtering KRYPTON sputtering pressure hydrogen adsorption performance
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