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Synthesis of p-type PbS quantum dot ink via inorganic ligand exchange in solution for high-efficiency and stable solar cells 被引量:1
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作者 Napasuda Wichaiyo Yuyao Wei +9 位作者 Chao Ding Guozheng Shi Witoon Yindeesuk Liang Wang Huān Bì Jiaqi Liu Shuzi Hayase Yusheng Li Yongge Yang Qing Shen 《Journal of Semiconductors》 2025年第4期63-70,共8页
Traditional p-type colloidal quantum dot(CQD)hole transport layers(HTLs)used in CQD solar cells(CQDSCs)are commonly based on organic ligands exchange and the layer-by-layer(LbL)technique.Nonetheless,the ligand detachm... Traditional p-type colloidal quantum dot(CQD)hole transport layers(HTLs)used in CQD solar cells(CQDSCs)are commonly based on organic ligands exchange and the layer-by-layer(LbL)technique.Nonetheless,the ligand detachment and complex fabrication process introduce surface defects,compromising device stability and efficiency.In this work,we propose a solution-phase ligand exchange(SPLE)method utilizing inorganic ligands to develop stable p-type lead sulfide(PbS)CQD inks for the first time.Various amounts of tin(Ⅱ)iodide(SnI_(2))were mixed with lead halide(PbX_(2);X=I,Br)in the ligand solution.By precisely controlling the SnI_(2)concentration,we regulate the transition of PbS QDs from n-type to p-type.PbS CQDSCs were fabricated using two different HTL approaches:one with 1,2-ethanedithiol(EDT)-passivated QDs via the LbL method(control)and another with inorganic ligand-passivated QD ink(target).The target devices achieved a higher power conversion efficiency(PCE)of 10.93%,compared to 9.83%for the control devices.This improvement is attributed to reduced interfacial defects and enhanced carrier mobility.The proposed technique offers an efficient pathway for producing stable p-type PbS CQD inks using inorganic ligands,paving the way for high-performance and flexible CQD-based optoelectronic devices. 展开更多
关键词 quantum dot solar cells hole transport layer PBS p-type ink inorganic ligands
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When Software Security Meets Large Language Models:A Survey 被引量:1
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作者 Xiaogang Zhu Wei Zhou +3 位作者 Qing-Long Han Wanlun Ma Sheng Wen Yang Xiang 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期317-334,共18页
Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, ... Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, software testing and analysis are two of the critical methods, which significantly benefit from the advancements in deep learning technologies. Due to the successful use of deep learning in software security, recently,researchers have explored the potential of using large language models(LLMs) in this area. In this paper, we systematically review the results focusing on LLMs in software security. We analyze the topics of fuzzing, unit test, program repair, bug reproduction, data-driven bug detection, and bug triage. We deconstruct these techniques into several stages and analyze how LLMs can be used in the stages. We also discuss the future directions of using LLMs in software security, including the future directions for the existing use of LLMs and extensions from conventional deep learning research. 展开更多
关键词 Large language models(LLMs) software analysis software security software testing
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NOTES ON THE LOG-MINKOWSKI INEQUALITY OF CURVATURE ENTROPY 被引量:1
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作者 Deyi LI Lei MA Chunna ZENG 《Acta Mathematica Scientia》 2025年第1期16-26,共11页
An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of c... An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of curvature entropy.As its application,a novel proof of the log-Minkowski inequality of curvature entropy in the plane is given. 展开更多
关键词 convex bodies the log-Minkowski inequality curvature entropy the log-Minkowski inequality of curvature entropy
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Potential mechanisms of non-coding RNA regulation in Alzheimer's disease 被引量:1
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作者 Yue Sun Xinping Pang +5 位作者 Xudong Huang Dinglu Liu Jingyue Huang Pengtao Zheng Yanyu Wei Chaoyang Pang 《Neural Regeneration Research》 2026年第1期265-280,共16页
Alzheimer's disease,a progressively degenerative neurological disorder,is the most common cause of dementia in the elderly.While its precise etiology remains unclear,researchers have identified diverse pathologica... Alzheimer's disease,a progressively degenerative neurological disorder,is the most common cause of dementia in the elderly.While its precise etiology remains unclear,researchers have identified diverse pathological characteristics and molecular pathways associated with its progression.Advances in scientific research have increasingly highlighted the crucial role of non-coding RNAs in the progression of Alzheimer's disease.These non-coding RNAs regulate several biological processes critical to the advancement of the disease,offering promising potential as therapeutic targets and diagnostic biomarkers.Therefore,this review aims to investigate the underlying mechanisms of Alzheimer's disease onset,with a particular focus on microRNAs,long non-coding RNAs,and circular RNAs associated with the disease.The review elucidates the potential pathogenic processes of Alzheimer's disease and provides a detailed description of the synthesis mechanisms of the three aforementioned non-coding RNAs.It comprehensively summarizes the various non-coding RNAs that have been identified to play key regulatory roles in Alzheimer's disease,as well as how these noncoding RNAs influence the disease's progression by regulating gene expression and protein functions.For example,miR-9 targets the UBE4B gene,promoting autophagy-mediated degradation of Tau protein,thereby reducing Tau accumulation and delaying Alzheimer's disease progression.Conversely,the long non-coding RNA BACE1-AS stabilizes BACE1 mRNA,promoting the generation of amyloid-βand accelerating Alzheimer's disease development.Additionally,circular RNAs play significant roles in regulating neuroinflammatory responses.By integrating insights from these regulatory mechanisms,there is potential to discover new therapeutic targets and potential biomarkers for early detection and management of Alzheimer's disease.This review aims to enhance the understanding of the relationship between Alzheimer's disease and non-coding RNAs,potentially paving the way for early detection and novel treatment strategies. 展开更多
关键词 Alzheimer's disease biomarkers circular RNA long non-coding RNA MICRORNA ncRNA regulation NEURODEGENERATION non-coding RNA PATHOGENESIS therapeutic targets
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A Study on the Learning Progressions of Understanding the Core Concepts of Kinetic Energy in High School
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作者 Xuemei Cui Yue Zheng Yu Chen 《Journal of Contemporary Educational Research》 2024年第11期46-55,共10页
Learning progressions divide the logical system of a subject into ordered and continuously developing levels that are suitable for the cognitive development level of students,which plays an important role in understan... Learning progressions divide the logical system of a subject into ordered and continuously developing levels that are suitable for the cognitive development level of students,which plays an important role in understanding students’learning process.This paper focuses on the theme of“kinetic energy”in high school physics as the research object.Firstly,the concept map was used to represent the relationship between knowledge,and then five core concepts were selected based on the opinions of high school teachers.Secondly,the test tools were compiled and tested based on the relevant test questions.Finally,the paper analyzed the results based on the Rasch model,clarified students’cognitive development level of“kinetic energy”and constructed the learning progressions of“kinetic energy”based on the logical order of subject knowledge.The research provides theoretical and methodological support for the study of other subjects and learning progressions,and provides a valuable reference for high school teachers to effectively carry out the instruction of“kinetic energy.” 展开更多
关键词 Core concepts High school Kinetic energy Learning progressions
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Statistical characteristics and classification of ionospheric mid-latitude trough as revealed by the observations of DMSP-F18
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作者 Yi Liu JiuHou Lei +1 位作者 FuQing Huang Su Zhou 《Earth and Planetary Physics》 EI CAS 2025年第1期137-147,共11页
Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program F18(DMSP-F18)satellite.T... Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program F18(DMSP-F18)satellite.The data was obtained at an altitude of around 860 km in near polar orbit,throughout 2013.Our study identified the auroral boundary based on the in-situ electron density and electron spectrum,allowing us to precisely determine the location of the mid-latitude trough.This differs from most previous works,which only use Total Electron Content(TEC)or in-situ electron density.In our study,the troughs exhibited a higher occurrence rate in local winter than in summer,and extended to lower latitudes with increasing geomagnetic activity.It was found that the ionospheric mid-latitude trough,which is associated with temperature changes or enhanced ion drift,exhibited distinct characteristics.Specifically,the ionospheric mid-latitude troughs related to electron temperature(Te)peak were located more equatorward of auroral oval boundary in winter than in summer.The ionospheric mid-latitude troughs related to Te-maximum were less frequently observed at 60−70°S magnetic latitude and 90−240°E longitude.Furthermore,the troughs related to ion temperature(Ti)maximums were observed at relatively higher latitudes,occurring more frequently in winter.In addition,the troughs related to ion velocity(Vi)maximums could be observed in all seasons.The troughs with the maximum-Ti and maximum-Vi were located closer to the equatorward boundary of the auroral oval at the nightside,and in both hemispheres.This implies that enhanced ion drift velocity contributes to increased collisional frictional heating and enhanced ion temperatures,resulting in a density depletion within the trough region. 展开更多
关键词 topside ionosphere mid-latitude trough ionospheric main trough auroral oval boundary temperature maximum
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Stabilization of clay soil using alkali-activated sewage sludge 被引量:1
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作者 Shahram Pourakbar Atiyeh Maneshmoaveni +3 位作者 Danial Moazami Laura Moretti Amirhossein Yousefi Nuno Cristelo 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期3213-3224,共12页
This study investigates the innovative reuse of sewage sludge with eco-friendly alkaline solutes to improve clayey soil without conventional cementitious binders.The unconfined compressive strength(UCS)was the main cr... This study investigates the innovative reuse of sewage sludge with eco-friendly alkaline solutes to improve clayey soil without conventional cementitious binders.The unconfined compressive strength(UCS)was the main criterion to assess the quality and effectiveness of the proposed solutions,as this test was performed to measure the strength of the stabilized clay by varying binders’dosages and curing times.Moreover,the direct shear test(DST)was used to investigate the Mohr-Coulomb parameters of the treated soil.Microstructure observations of the natural and treated soil were conducted using scanning electron microscope(SEM),energy-dispersive spectroscopy(EDS),and FTIR.Furthermore,toxicity characteristic leaching procedure(TCLP)tests were performed on the treated soil to investigate the leachability of metals.According to the results,using 2.5%of sewage sludge activated by NaOH and Na_(2)SiO_(3)increases the UCS values from 176 kPa to 1.46 MPa after 7 d and 56 d of curing,respectively.The results of the DST indicate that sewage sludge as a precursor increases cohesion and enhances frictional resistance,thereby improving the Mohr-Coulomb parameters of the stabilized soil.The SEM micrographs show that alkali-activated sewage sludge increases the integrity and reduces the cavity volumes in the stabilized soil.Moreover,TCLP tests revealed that the solubility of metals in the treated soil alkaliactivated by sewage sludge significantly decreased.This study suggests that using sewage sludge can replace cement and lime in ground improvement,improve the circular economy,and reduce the carbon footprint of construction projects. 展开更多
关键词 Soil stabilization Toxicity leaching Alkaline activation Sewage sludge Ground improvement
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The Security of Using Large Language Models:A Survey With Emphasis on ChatGPT 被引量:1
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作者 Wei Zhou Xiaogang Zhu +4 位作者 Qing-Long Han Lin Li Xiao Chen Sheng Wen Yang Xiang 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期1-26,共26页
ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential sec... ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential security risks that need to be carefully evaluated and addressed. In this survey, we provide an overview of the current state of research on security of using ChatGPT, with aspects of bias, disinformation, ethics, misuse,attacks and privacy. We review and discuss the literature on these topics and highlight open research questions and future directions.Through this survey, we aim to contribute to the academic discourse on AI security, enriching the understanding of potential risks and mitigations. We anticipate that this survey will be valuable for various stakeholders involved in AI development and usage, including AI researchers, developers, policy makers, and end-users. 展开更多
关键词 Artificial intelligence(AI) ChatGPT large language models(LLMs) SECURITY
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Variations of soil moisture and its influencing factors in arid and semi-arid areas,China 被引量:1
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作者 NIU Jiqiang LIU Zijian +5 位作者 CHEN Feiyan LIU Gangjun ZHOU Junli ZHOU Peng LI Hongrui LI Mengyang 《Journal of Arid Land》 2025年第5期624-643,共20页
Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influenci... Soil moisture(SM)is a critical variable in terrestrial ecosystems,especially in arid and semi-arid areas where water sources are limited.Despite its importance,understanding the spatiotemporal variations and influencing factors of SM in these areas remains insufficient.This study investigated the spatiotemporal variations and influencing factors of SM in arid and semi-arid areas of China by utilizing the extended triple collation(ETC),Mann-Kendall test,Theil-Sen estimator,ridge regression analysis,and other relevant methods.The following findings were obtained:(1)at the pixel scale,the long-term monthly SM data from the European Space Agency Climate Change Initiative(ESA CCI)exhibited the highest correlation coefficient of 0.794 and the lowest root mean square error(RMSE)of 0.014 m^(3)/m^(3);(2)from 2000 to 2022,the study area experienced significant increase in annual average SM,with a rate of 0.408×10^(-3)m^(3)/(m^(3)•a).Moreover,higher altitudes showed a notable upward trend,with SM increasing rates at 0.210×10^(-3)m^(3)/(m^(3)•a)between 1000 and 2000 m,0.530×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m,and 0.760×10^(-3)m^(3)/(m^(3)•a)at altitudes above 4000 m;(3)land surface temperature(LST),root zone soil moisture(RSM)(10-40 cm depth),and normalized difference vegetation index(NDVI)were identified as the primary factors influencing annual average SM,which accounted for 34.37%,24.16%,and 22.64%relative contributions,respectively;and(4)absolute contribution of LST was more significant in subareas at higher altitudes,with average absolute contributions of 0.800×10^(-3)m^(3)/(m^(3)•a)between 2000 and 4000 m and 0.500×10^(-2) m^(3)/(m^(3)•a)above 4000 m.This study reveals the spatiotemporal variations and main influencing factors of SM in Chinese arid and semi-arid areas,highlighting the more pronounced absolute contribution of LST to SM in high-altitude areas,providing valuable insights for ecological research and water resource management in these areas. 展开更多
关键词 soil moisture arid and semi-arid areas remote sensing extended triple collation ridge regression analysis
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Inhibitory effect of the interlayer of two-dimensional vermiculite on the polysulfide shuttle in lithium-sulfur batteries
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作者 CHEN Xiaoli LUO Zhihong +3 位作者 XIONG Yuzhu WANG Aihua CHEN Xue SHAO Jiaojing 《无机化学学报》 北大核心 2025年第8期1661-1671,共11页
A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface... A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface area of 427 m^(2)·g^(-1)and rich surface active sites,which help restrain polysulfides(LiPSs)through good physi-cal and chemical adsorption,while simultaneously accelerating the nucleation and dissolution kinetics of Li_(2)S,effec-tively suppressing the shuttle effect.The assembled lithium-sulfur batteries(LSBs)employing the PVS-based inter-layer delivered a high initial discharge capacity of 1386 mAh·g^(-1)at 0.1C(167.5 mAh·g^(-1)),long-term cycling stabil-ity,and good rate property. 展开更多
关键词 vermiculite nanosheets two-dimensional materials INTERLAYER shuttle effect lithium-sulfur batteries
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Exceptional Set for Diophantine Approximation with Primes of Two Squares and Three Biquadrates
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作者 LIU Minmin ZHANG Min LI Jinjiang 《数学进展》 北大核心 2025年第1期18-36,共19页
Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for ... Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for anyε>0,the number of v∈V with v≤N such that the following inequality|λ_(1)p_(1)~2+λ_(2)p_(2)~2+λ_(3)p_(3)~4+λ_(4)p_(4)~4+λ_5p_5~4-v|<v^(-δ)has no solution in prime variables p_(1),p_(2),p_(3),p_(4),p_(5)does not exceed O(N^(29/32+2δ+ε)). 展开更多
关键词 Diophantine approximation exponential sum Davenport-Heilbronn method prime variable
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Compactness of Fractional Calderón Type Commutators on Morrey Spaces
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作者 LI Aobo MEI Ting WEI Qi 《数学进展》 北大核心 2025年第4期858-870,共13页
In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey... In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey spaces L^(p,λ)(R^(n)). 展开更多
关键词 Calderón type commutator COMPACTNESS Log-type Dini-condition Morrey space
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Molecular Structure Tailoring of Organic Spacers for High‑Performance Ruddlesden–Popper Perovskite Solar Cells
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作者 Pengyun Liu Xuejin Li +6 位作者 Tonghui Cai Wei Xing Naitao Yang Hamidreza Arandiyan Zongping Shao Shaobin Wang Shaomin Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期314-357,共44页
Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(P... Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(PSC)technology.However,two-dimensional(2D)or quasi-2D RP PSCs are encountered with some challenges of the large exciton binding energy,blocked charge transport and poor film quality,which restrict their photovoltaic performance.Fortunately,these issues can be readily resolved by rationally designing spacer cations of RPPs.This review mainly focuses on how to design the molecular structures of organic spacers and aims to endow RPPs with outstanding photovoltaic applications.We firstly elucidated the important roles of organic spacers in impacting crystallization kinetics,charge transporting ability and stability of RPPs.Then we brought three aspects to attention for designing organic spacers.Finally,we presented the specific molecular structure design strategies for organic spacers of RPPs aiming to improve photovoltaic performance of RP PSCs.These proposed strategies in this review will provide new avenues to develop novel organic spacers for RPPs and advance the development of RPP photovoltaic technology for future applications. 展开更多
关键词 Ruddlesden-Popper perovskites Low-dimensional perovskite solar cells Organic spacers Molecular structure Design strategies
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Preparation and Modification of MXene Composites for Application in Electrochemical Energy Storage
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作者 Zhang-Hai You Ding-Ze Lu +5 位作者 Kiran Kumar Kondamareddy Wen-Ju Gu Peng-Fei Cheng Jing-Xuan Yang Rui Zheng Hong-Mei Wang 《电化学(中英文)》 北大核心 2025年第5期1-27,共27页
With the acceleration of advanced industrialization and urbanization,the environment is deteriorating rapidly,and non-renewable energy resources are depleted.The gradual advent of potential clean energy storage techno... With the acceleration of advanced industrialization and urbanization,the environment is deteriorating rapidly,and non-renewable energy resources are depleted.The gradual advent of potential clean energy storage technologies is particularly urgent.Electrochemical energy storage technologies have been widely used in multiple fields,especially supercapacitors and rechargeable batteries,as vital elements of storing renewable energy.In recent years,two-dimensional material MXene has shown great potential in energy and multiple application fields thanks to its excellent electrical properties,large specific surface area,and tunability.Based on the layered materials of MXene,researchers have successfully achieved the dual functions of energy storage and conversion by adjusting the surface terminals at the Fermi level.It is worth noting that compared with other two-dimensional materials,MXene has more active sites on the basal plane,showing excellent catalytic performance.In contrast,other two-dimensional materials have catalytic activity only at the edge sites.This article comprehensively overviews the synthesis process,structural characteristics,modification methods for MXene-based polymer materials,and their applications in electrochemical energy storage.It also briefly discusses the potential of MXene-polymer materials in electromagnetic shielding technology and sensors and looks forward to future research directions. 展开更多
关键词 MXene Preparation process Modification strategy Electrochemical energy storage
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Effects of Sc Content on Microstructure and Thermophysical Properties of Al-xSc Alloys
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作者 Wu Daogao Zhang Lu +8 位作者 Xu Minglei Feng Jing Li Shuan Zhang Xiaowei Wang Zhiqiang Yang Hongbo Dong Ruifeng Chen Xihao Wang Ning 《稀有金属材料与工程》 北大核心 2025年第9期2220-2230,共11页
AlScN piezoelectric films prepared by AlSc alloy sputter targets are essential materials for 5G radio frequency filters.The thermophysical properties of AlSc alloy targets are closely related to their welding processe... AlScN piezoelectric films prepared by AlSc alloy sputter targets are essential materials for 5G radio frequency filters.The thermophysical properties of AlSc alloy targets are closely related to their welding processes and applications.Al-xSc alloys(x=5,10,15,20,25,at%)were prepared by vacuum induction melting,whose purity is mainly determined by the raw materials and the production process.The results reveal that as the Sc content increases from 5at%to 20at%,the volume fraction of the Al_(3)Sc phase in the alloy increases from 26.9%to 80.2%,and the average grain size of the Al_(3)Sc phase increases from 12.9μm to 67.7μm during this period.Additionally,both the coefficient of thermal expansion(CTE)and thermal conductivity(TC)of AlSc alloys exhibit a downward trend.Based on experimental data and first-principles calculations,the effective medium theory and the Turner model effectively predict the TC and CTE of Al-xSc alloys.The optimal characteristic parameter(k0)of the Turner model is determined to be 50.The model predictions align well with the experimental results. 展开更多
关键词 AlSc alloys first principles MICROSTRUCTURE thermophysical properties
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High-Temperature Oxidation Property and Corrosion and Wear Resistance of Laser Cladding Co-based Coatings on Pure Zr Surface
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作者 Xia Chaoqun Yang Bo +3 位作者 Liu Shuguang Zhang Bo Zhong Hua Li Qiang 《稀有金属材料与工程》 北大核心 2025年第6期1397-1409,共13页
Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,a... Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution. 展开更多
关键词 Zr metal laser cladding Co-based coating high-temperature oxidation resistance wear resistance
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A dengue epidemic model with the impact of media influence
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作者 QIAO Xia ZHANG Tai-lei HOU Yue 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第1期238-254,共17页
In this paper,we establish an ShIhAhSvIvW model to investigate the impact of media communication on the transmission mechanism of dengue fever.Firstly,the basic reproduction number R0of the model is obtained by using ... In this paper,we establish an ShIhAhSvIvW model to investigate the impact of media communication on the transmission mechanism of dengue fever.Firstly,the basic reproduction number R0of the model is obtained by using the method of the next generation matrix.It shows that disease-free equilibrium is globally asymptotically stable when R0<1;the disease is uniformly persistent when R_(0)>1.Secondly,we select dengue fever case data from Guangdong Province from 2006 to 2019 for numerical simulations and predict its development trend.Finally,we conduct parameter sensitivity analysis,and the results show that increasing media publicity can to some extent reduce the number of patients. 展开更多
关键词 dengue fever basic reproduction number uniform persistence media factors numerical predic-tion
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On New Generalizations of Hermite-Hadamard Inequalities via(p,q)-Integral
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作者 LIU Xue CHENG Li-hua 《Chinese Quarterly Journal of Mathematics》 2025年第2期211-220,共10页
This paper presents new generalizations of the Hermite-Hadamard inequality for convex functions via(p,q)-quantum integrals.First,based on the definitions of(p,q)-derivatives and integrals over finite intervals,we esta... This paper presents new generalizations of the Hermite-Hadamard inequality for convex functions via(p,q)-quantum integrals.First,based on the definitions of(p,q)-derivatives and integrals over finite intervals,we establish a unified(p,q)-Hermite-Hadamard inequality framework,combining midpoint-type and trapezoidal-type inequalities into a single form.Furthermore,by introducing a parameterλ,we propose a generalized(p,q)-integral inequality,whose special cases reduce to classical quantum Hermite-Hadamard inequalities and existing results in the literature.Furthermore,using hybrid integral techniques,we construct refined inequalities that incorporate(p,q)-integral terms,and by adjustingλ,we demonstrate their improvements and extensions to known inequalities.Specific examples are provided to validate the applicability of the results.The findings indicate that the proposed(p,q)-integral approach offers more flexible mathematical tools for the estimation of numerical integration error,convex optimization problems,and analysis of system performance in control theory,thus enriching the research results of quantum calculus in the field of inequalities. 展开更多
关键词 Hermite-Hadamard inequality (p q)-integral (p q)-derivative Convex functions Quantum calculus
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Experimental Investigation on the Mechanical Properties of Silicone Elastomers Filled with Fumed Silica for Seismic Isolation Bearings
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作者 Arthur Ramandalina Ji Dang 《Journal of Building Material Science》 2025年第1期44-61,共18页
Laminated elastomeric bearings used in seismic isolation rely on the mechanical properties of their constituent elastomers to ensure effective performance.However,despite their resistance to temperature fluctuations a... Laminated elastomeric bearings used in seismic isolation rely on the mechanical properties of their constituent elastomers to ensure effective performance.However,despite their resistance to temperature fluctuations and environmental aggressors,silicone elastomers exhibit relatively low stiffness,limiting their direct applicability in seismic isolation.This study investigates the effect of fumed silica as a reinforcing filler to enhance the mechanical properties of laminated silicone elastomeric bearings.Elastomeric samples were fabricated with varying fumed silica proportions and subjected to Shore A hardness,uniaxial tensile,and lap shear tests to assess the influence of filler content.Additionally,quasi-static tests were conducted on reduced-scale bearing prototypes under combined vertical compression and cyclic horizontal shear to evaluate their seismic isolation performance.The results demonstrate that fumed silica reinforcement significantly increases stiffness,as evidenced by higher Shore A hardness values.However,a trade-off was observed in tensile properties,with reductions in tensile strength and elongation at break.Despite this,the equivalent elastic modulus did not show substantial variation up to large deformations,indicating that stiffness is preserved under most working conditions.Lap shear tests showed that fumed silica improves shear resistance,while quasi-static tests revealed inelastic behavior with small increases in equivalent shear coefficients but no substantial loss in damping ratios.These findings suggest that fumed silica reinforcement enhances silicone elastomers’stiffness and shear resistance while maintaining moderate damping properties,making it a promising approach for improving the mechanical performance of elastomeric bearings in seismic isolation applications. 展开更多
关键词 Silicone Elastomer Fumed Silica Elastomeric Bearing Seismic Isolation Experimental Study
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Reform and Practice of Ideological and Political Education in Advanced Mathematics under the OBE Concept
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作者 Zejun Wang Mei Yang Peng Ma 《Journal of Contemporary Educational Research》 2025年第9期420-424,共5页
In the context of the new era of education,advanced mathematics not only undertakes the function of knowledge transmission but also plays a vital role in cultivating logical thinking,scientific spirit,and value orient... In the context of the new era of education,advanced mathematics not only undertakes the function of knowledge transmission but also plays a vital role in cultivating logical thinking,scientific spirit,and value orientation.However,traditional teaching has overemphasized knowledge instillation while neglecting value guidance,making it difficult to meet the demands of cultivating interdisciplinary talents.This study introduces the OBE concept and constructs a“knowledge–ability–value”teaching framework,integrating outcome orientation,backward design,and diversified evaluation to promote the systematic incorporation of ideological and political education into the curriculum.Taking limits,definite integrals,and series as representative knowledge points,the paper designs case-based pathways to foster dialectical thinking,patriotism,and scientific spirit.Practice has shown that this model effectively unifies knowledge education and value education,enhancing students’logical reasoning,sense of responsibility,and scientific literacy.The study provides an operational pathway for the reform of ideological and political education in advanced mathematics courses and carries practical significance for implementing the goal of“all-round education.” 展开更多
关键词 OBE concept Advanced mathematics Ideological and political education Teaching reform Case-based teaching
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