期刊文献+
共找到1,444篇文章
< 1 2 73 >
每页显示 20 50 100
Potential mechanisms of non-coding RNA regulation in Alzheimer's disease 被引量:2
1
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
暂未订购
Iron-Involved ORR Electrocatalysts under the Lens of In-Situ/Operando Mössbauer Spectroscopy
2
作者 Sumbal Farid Jun-Hu Wang 《电化学(中英文)》 北大核心 2026年第1期42-64,共23页
Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements hav... Exploring cost-effective and efficient catalysts for oxygen reduction reaction(ORR)poses a significant challenge,espe-cially in the pursuit of alternatives to precious metals like platinum.Significant advancements have driven electrochem-ists to develop efficient ORR catalysts using abundant materials,particularly iron(Fe)-based,known for their exceptional performance in ORR.While the crucial function of Fe in boosting ORR catalytic activity is recognized,the connection between material attributes and catalytic performance remains enigmatic.Understanding the dynamic processes involved in oxygen electrocatalysis is paramount for designing precious-metals-free ORR electrocatalysts.Mössbauer spectroscopy stands out as a powerful technique for deciphering the structural characteristics of Fe species in catalysis,facilitating the identification of active sites and the clarification of catalytic mechanisms.By showcasing noteworthy case studies within this review,we demonstrate the application of in-situ/operando 57Fe Mössbauer spectroscopy across diverse Fe-involved materials in ORR catalysis.This sheds light on various aspects of ORR catalysis,such as identifying active sites,assessing stability,and understanding the reaction mechanism.Our inquiry drives towards the opportunities and hurdles associ-ated with Mössbauer spectroscopy,unveiling potential breakthroughs and avenues for enhancement within this pivotal research realm. 展开更多
关键词 Iron-based electrocatalyst In-situ/operando analysis Mössbauer spectroscopy Oxygen reduction reaction Structure-activity relationship
在线阅读 下载PDF
A review of nanodiamond-based photocatalysts for solar energy conversion
3
作者 Zhang Wan Cheng Xiangxiang +5 位作者 Guo Kesheng Zhang Hansong Li Lanxiao Zhao Yongbing Zhu Jiaqi Wang Yongjie 《新型炭材料(中英文)》 北大核心 2026年第1期18-43,共26页
Photocatalysis is an important technology for using solar energy to produce hydrogen,convert CO_(2) to synthetic fuels,and decrease persistent pollutant.However,conventional photocatalysts have limitations,including p... Photocatalysis is an important technology for using solar energy to produce hydrogen,convert CO_(2) to synthetic fuels,and decrease persistent pollutant.However,conventional photocatalysts have limitations,including poor spectral absorption,inefficient charge separation,and structural instability under operational stress,which demand innovative durable materials with tailored electronic properties.Nanodiamond(ND)has recently been recognized as a suitable material because of its exceptional chemical stability,superior charge carrier mobility,and possible surface functionalization.While its intrinsic wide bandgap limits its response to visible-light,different methods have been demonstrated to activate its catalytic potential.Here,several emerging strategies for improving the catalytic performance of ND-based photocatalytic systems are summarized,including surface functionalization,plasmonic hybridization,heteroatom doping,and heterostructure design.And the structure-activity relationship and design principle are proposed to improve the light harvesting,charge transport,and redox kinetics for constructing high efficiency ND-based photocatalysts used in the renewable energy and environmental industries. 展开更多
关键词 PHOTOCATALYSIS NANODIAMOND Solar fuel conversions FUNCTIONALIZATION DOPING HETEROSTRUCTURE
在线阅读 下载PDF
Spatiotemporal Heterogeneity and Key Driving Factors of Ecological Land Fragmentation in Guanzhong Plain Urban Agglomeration,China
4
作者 DONG Yong ZHOU Liang +3 位作者 CHE Tao GAO Hong SUN Qinke WANG Wenda 《Chinese Geographical Science》 2025年第6期1392-1410,共19页
Due to the multiple impacts of global climate change and anthropogenic disturbances,regional ecological landscapes have been developing towards fragmentation.How to quantitatively measure regional ecological landscape... Due to the multiple impacts of global climate change and anthropogenic disturbances,regional ecological landscapes have been developing towards fragmentation.How to quantitatively measure regional ecological landscape fragmentation and identify its key drivers is an important foundation for regional biodiversity conservation and ecosystem restoration.Taking the Guanzhong Plain Urban Agglomeration(GPUA),China as the research object,this paper proposes a comprehensive framework that integrates landscape pattern index,principal component analysis,random forest(RF)and other methods to quantitatively analyze the spatial and temporal evolution of ecological landscape fragmentation and its driving factors.The results show that:1)cropland,forestland and grassland showed significant spatial differentiation in the landscape pattern index,and the change of their mean values indicated that cropland and forestland show a trend of‘little decrease-continuous increase’.Spatially,the northwestern and southeastern regions showed significant fragmentation and prominent spatial heterogeneity.2)From 2010 to 2020,the landscape fragmentation of cropland and forestland increased by 71%and 20%,respectively,while that of grassland decreased by 33%,indicating that the degree of landscape fragmentation of cropland changed more drastically than that of other ecological land.3)It was found that slope was the most important factor affecting landscape fragmentation of ecological land.In addition,road density had a significant effect on landscape fragmentation of cropland and forestland,but the min-distance between patches and the county center had an important effect on landscape fragmentation of grassland.This study can provide theoretical references for urban agglomeration planning and sustainable landscape management on a regional scale. 展开更多
关键词 ecological landscape FRAGMENTATION random forest(RF) driving factors Guanzhong Plain Urban Agglomeration of China(GPUA)
在线阅读 下载PDF
CRISPR/Cas9-mediated dysfunction of pectate lyase MaPL11 enhances postharvest shelf-life in banana
5
作者 Tongxin Dou Chunhua Hu +9 位作者 Qiufeng Zhong Fei Qin Ou Sheng Qiaosong Yang Guiming Deng Weidi He Huijun Gao Tao Dong Ganjun Yi Fangcheng Bi 《Horticultural Plant Journal》 2026年第2期481-484,共4页
Banana(Musa spp.)is one of the most important fruit crop worldwide,and plays a critical role in human diet and agricultural economies across tropical and subtropical regions,including China(Jiang et al.,2025;Wu et al.... Banana(Musa spp.)is one of the most important fruit crop worldwide,and plays a critical role in human diet and agricultural economies across tropical and subtropical regions,including China(Jiang et al.,2025;Wu et al.,2025).However,its rapid softening severely limits shelf life,causing substantial economic losses during transport and storage.Recently,the enhanced shelf-life can be generated by compromising the key ripening regulators,such as RIN,but other fruit quality traits including flavor and color also can be impaired concurrently(Kitagawa et al.,2005). 展开更多
关键词 fruit crop BANANA Postharvest Shelf Life MAPL Crispr Cas Pectate Lyase Ripening Regulators Musa spp
在线阅读 下载PDF
Numerical Simulation of the Welding Deformation of Marine Thin Plates Based on a Temperature Gradient-thermal Strain Method
6
作者 Lin Wang Yugang Miao +3 位作者 Zhenjian Zhuo Chunxiang Lin Benshun Zhang Duanfeng Han 《哈尔滨工程大学学报(英文版)》 2026年第1期122-135,共14页
Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The t... Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates. 展开更多
关键词 Marine thin plate Welding deformation Numerical simulation Temperature gradient-thermal strain method Shell element
在线阅读 下载PDF
Microstructure and the corrosion resistance of SiC reinforced pyrolytic graphite coating under physical vapor transport SiC environment
7
作者 TAO Xian-cheng SUN Wei +3 位作者 SUN Ye-hua DENG Nan-jun WANG Zi-wei XIONG Xiang 《Journal of Central South University》 2026年第1期131-143,共13页
In order to effectively prevent the contamination of carbon particle volatiles during high-purity SiC crystals are prepared using the physical vapor transport(PVT)method in ultra-high temperature environments(T³2... In order to effectively prevent the contamination of carbon particle volatiles during high-purity SiC crystals are prepared using the physical vapor transport(PVT)method in ultra-high temperature environments(T³2000℃),this study innovatively attempts to protect graphite materials with SiC reinforced pyrolytic graphite(PyG)coating.It is discovered by preparing the SiC particle layer,the degree of graphitization and stability of PyG coating can be improved.The corrosion test results demonstrated that the SiC reinforced PyG coating can maintain an intact coating with a high graphitization degree after the SiC vapour corrosion test of 2050℃-120 h.Conversely,the samples with and without PyG coating reveal porous and eroded surfaces.Furthermore,following the SiC vapour corrosion test,the PyG coating sample’s integral ratio of D-band and G-band(I_(D)/I_(G))of Raman spectrum test data,reduced by 6.5%,while the SiC reinforced PyG coating decreased by 17.2%,indicating its excellent corrosion resistance.The application of SiC reinforced pyrolytic graphite coating in preparing the SiC single crystal might received a theoretical foundation according to this work. 展开更多
关键词 pyrolytic graphite silicon carbide chemical vapour reaction high-temperature chemical vapour deposition SiC crystal growth corrosion resistance
在线阅读 下载PDF
Constructions of Control Sequence Set for Hierarchical Access in Data Link Network
8
作者 Niu Xianhua Ma Jiabei +3 位作者 Zhou Enzhi Wang Yaoxuan Zeng Bosen Li Zhiping 《China Communications》 2026年第1期67-80,共14页
As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and ... As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities. 展开更多
关键词 control sequence data link hierarchical access control theoretical bound
在线阅读 下载PDF
Weakening aging-induced embrittlement via deformation-assisted regulation of isothermal ω precipitation in metastable Ti−15Mo alloy
9
作者 Fei ZHANG Shi-wei PAN +4 位作者 Shun XU Feng QIAN Jiang-kun FAN Qun-bo FAN Xing-wang CHENG 《Transactions of Nonferrous Metals Society of China》 2026年第1期144-155,共12页
In order to overcome the embrittlement of metastable titanium alloys caused by the precipitation ofωiso phase during aging,regulation of isothermalωprecipitation was investigated in Ti−15Mo alloy.The results show th... In order to overcome the embrittlement of metastable titanium alloys caused by the precipitation ofωiso phase during aging,regulation of isothermalωprecipitation was investigated in Ti−15Mo alloy.The results show that the sample is brittle when direct aging(A)is applied at 350℃for 1 h after solution treatment(ST).If pre-deformation(D)is performed on the ST sample to induce{332}twins and secondaryα″phase,subsequent aging at 350℃(STDA350)improves the strength to 931 MPa with a good ductility of about 20%maintained.However,when aging is performed at 400℃or 450℃(STDA400/450),the strength can be further improved,but the ductility is dramatically reduced.Atomic-scale characterizations show that the partial collapse ofωphase in the STDA350 sample effectively eliminates aging-induced embrittlement,but complete collapse leads to poor ductility in the STDA400/450 sample. 展开更多
关键词 room-temperature mechanical property structural collapse ωphase aging-induced embrittlement Ti−15Mo alloy
在线阅读 下载PDF
Micropolar homogenization constitutive modeling and size effect analysis of lattice materials
10
作者 Tingrui CHEN Fan YANG +2 位作者 Jingchun ZHANG Dong HAN Qingcheng YANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期39-60,共22页
Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenizatio... Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenization methods based on the classical elasticity theory struggle to accurately describe the non-classical mechanical behaviors of lattice materials,especially when dealing with complex unit-cell geometries featured by non-symmetric configurations or non-single central node connections.In response to this limitation,this study establishes a generalized homogenization model based on the micropolar theory framework,employing Hill's boundary conditions to precisely predict the equivalent moduli of complex lattice materials.By introducing the independent rotational degree of freedom(DOF)characteristic of the micropolar theory,the proposed model successfully overcomes the limitation of conventional methods in accurately describing the asymmetric deformation and scale effects.We initially calculate the constitutive relations of two-dimensional(2D)cross-shaped multi-node chiral lattices and subsequently extend the method to three-dimensional(3D)lattices,successfully predicting the mechanical properties of both traditional and eccentric body-centered cubic(BCC)lattices.The theoretical model is validated through the finite element numerical verification which shows excellent consistency with the theoretical predictions.A further parametric study investigates the influence of geometric parameters,revealing the underlying size-effect mechanism.This paper provides a reliable theoretical tool for the design and property optimization of complex lattice materials. 展开更多
关键词 lattice material size effect micropolar theory homogenization method constitutive relationship
在线阅读 下载PDF
Optimal design,microstructures and mechanical properties of electrically-assisted extrusion of magnesium alloys micro-grooved heat pipes
11
作者 Xiaoliang WANG Xiaoming WANG +4 位作者 Yongda LIU Haibao LU Debin SHAN Bin GUO Jie XU 《Science China(Technological Sciences)》 2026年第2期207-219,共13页
Developing precision forming of magnesium alloy micro-grooved heat pipes is of great significance for improving the lightweight level of aerospace thermal management systems.In this paper,the electrically-assisted ext... Developing precision forming of magnesium alloy micro-grooved heat pipes is of great significance for improving the lightweight level of aerospace thermal management systems.In this paper,the electrically-assisted extrusion of magnesium alloy heat pipes is explored,and the effects of extrusion and electrical parameters on the forming accuracy,microstructures,and mechanical properties are studied.Finite element simulation found that electrifying the extrusion ram and preheating the extrusion cylinder could effectively ensure the billet temperature,and an extrusion window(30-60 s)could be obtained.Reducing the extrusion velocity and increasing the current could both reduce the extrusion load.Within the range of the studied parameters,the micro-grooved heat pipes are relatively fully formed.It is found that increasing the extrusion velocity and electrical parameters would increase the grain size of the magnesium alloy.While the electrical parameter increases from 0 to 300 A,the grain size increases from~5.9 to~12.6μm,and the tensile strength and yield strength of the extruded profiles are also 20.7%and 16.8%lower than those without current.The tensile fracture surface shows that under the parameters of high extrusion velocity and high current,the fracture morphology changes from dimples and cleavage planes to large-area river patterns,and the fracture mode changes from the mixed ductile-brittle fracture to the brittle fracture.Under the extrusion parameters of 0.5 mm/s and 100 A,the extrusion load is reduced by 1.0-1.6 T,the cross-sectional filling rate is as high as 97.5%,and the size deviation of the micro-ribs(0.8 mm)is only±5μm.Simultaneously,under these parameters,the grain size does not significantly coarsen,and the strength and plasticity of the heat pipe increase slightly.This work provides theoretical and technical support for the development of precision forming technology of lightweight aerospace heat pipes. 展开更多
关键词 micro-grooved heat pipe electrically-assisted extrusion forming precision MICROSTRUCTURES mechanical properties
原文传递
Microstructure evolution and mechanical properties of spray-formed 7055 Al alloy subjected to cryogenic rolling
12
作者 Tian ZHOU Yang-wei WANG +5 位作者 Jia-wei BAO Muhammad Abubaker KHAN Ping-luo ZHAO Rui AN Hao ZHANG Mohamed A.AFIFI 《Transactions of Nonferrous Metals Society of China》 2026年第2期386-400,共15页
Cryogenic rolling impacts on microstructure and mechanical properties of spray-formed 7055(SF-7055)Al alloy were investigated.Results show that with the increase of the reduction from 20%to 80%,the grain of cryogenic ... Cryogenic rolling impacts on microstructure and mechanical properties of spray-formed 7055(SF-7055)Al alloy were investigated.Results show that with the increase of the reduction from 20%to 80%,the grain of cryogenic rolled SF-7055 Al alloy is elongated to form a fiber texture.Numerous proliferating dislocations in the microstructure accumulate into dislocation walls and cells,and eventually form subgrains.These subgrain boundaries divide the original grain,thereby reducing the grain size.Under severe deformation conditions,they even enable the formation of nanograins.Meanwhile,the Cu-rich precipitates in the matrix are also broken and refined under the action of large rolling stress.In the process of cryogenic rolling,the tensile strength and hardness of SF-7055 Al alloy gradually increase,while the plasticity decreases.Moreover,the fracture morphology of cryogenic rolled SF-7055 Al alloy gradually transforms to the ductile and quasi-cleavage hybrid fracture characteristics with increased reduction. 展开更多
关键词 spray-formed Al alloy cryogenic rolling microstructure mechanical properties NANOGRAINS
在线阅读 下载PDF
Ultrasonic vibration-assisted cutting of titanium alloys:A state-of-the-art review 被引量:3
13
作者 Ahmar KHAN Xin WANG +7 位作者 Biao ZHAO Wenfeng DING Muhammad JAMIL Aqib Mashood KHAN Syed Hammad ALI Sadam HUSSAIN Jiong ZHANG Raj DAS 《Chinese Journal of Aeronautics》 2025年第1期3-42,共40页
The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and med... The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and medical sectors.However,conventional machining of titanium alloys leads to elevated tool wear,development of surface defects,and reduced machining efficiency due to their low heat conductivity,and chemical affinity.These issues can be somewhat counteracted by integrating ultrasonic vibration in the conventional machining of titanium alloys and also enhance sustainability.This review article offers a holistic evaluation of the influence of ultrasonic vibration-assisted milling and turning on cutting forces,temperature,tool wear,and surface integrity,encompassing surface morphology,surface roughness,surface residual stress,surface hardness,and surface tribological properties during titanium alloys machining.Furthermore,it investigates the sustainability aspect that has not been previously examined.Studies on the performance of ultrasonic-assisted cutting revealed several advantages,including decreased cutting forces and cutting temperature,improved tool life,and a better-machined surface during machining.Consequently,the sustainability factor is improved due to minimized energy consumption and residual waste.In conclusion,the key challenges and future prospects in the ultrasonic-assisted cutting of titanium alloys are also discussed.This review article provides beneficial knowledge for manufactur-ers and researchers regarding ultrasonic vibration-assisted cutting of titanium alloy and will play an important role in achieving sustainability in the industry. 展开更多
关键词 Ultrasonic vibration-assisted cutting Titanium alloys Material removal mechanism MACHINABILITY SUSTAINABILITY
原文传递
Synergy of strength-ductility in a novel Al-Zn-Mg-Cu-Zr-Sc-Hf alloy through optimizing hierarchical microstructures 被引量:1
14
作者 Mingdong Wu Daihong Xiao +5 位作者 Shuo Yuan Zeyu Li Xiao Yin Juan Wang Lanping Huang Wensheng Liu 《Journal of Materials Science & Technology》 2025年第9期105-122,共18页
The strength improvement in the heat-treatable Al-Zn-Mg-Cu alloys is generally achieved by increasing the volume fraction of nanoprecipitates and reducing the grain size.However,utilizing one of them usu-ally leads to... The strength improvement in the heat-treatable Al-Zn-Mg-Cu alloys is generally achieved by increasing the volume fraction of nanoprecipitates and reducing the grain size.However,utilizing one of them usu-ally leads to a drastic decrease in ductility.Herein,we architect a hierarchical microstructure integrating bimodal grain structures,nanoprecipitates,and hard-brittle coarse particles wrapped by ductility coarse grain(CG)bands via conventional cold rolling(CR)deformation and heat treatment methods to break the strength-ductility dilemma in the Al-8.89Zn-1.98Mg-2.06Cu-0.12Zr-0.05Sc-0.05Hf(wt.%)alloy.The results reveal that the coupling of high-volume fraction(∼1.2%)nanoprecipitates,∼52%narrow CG bands,and most coarse particles encapsulated by CG bands contribute to the 45%CR sample with outstanding over-all mechanical properties(a tensile strength of 655 MPa,a yield strength of 620 MPa,and an elongation of 15.5%).Microstructure-based strength analysis confirms that the high strength relates to a trade-offbetween the hierarchical features,namely high-volume fraction nanoprecipitates to counterbalance the strength loss caused by grain coarsening.The excellent ductility is due to the introduction of medium CG content with a narrow width that can trigger a cross-scale strain distribution during plastic deforma-tion,suppressing the catastrophic failure in the fine grain(FG)regions and facilitating the dimple fracture along the CG bands.This study proposes a feasible approach for tailoring hierarchical microstructures in Al-Zn-Mg-Cu alloys to achieve a superior strength-ductility combination. 展开更多
关键词 Al-Zn-Mg-Cu alloy Bimodal grain structures Nanoprecipitates Coarse particles Mechanical properties
原文传递
Atomic-scale investigation on the evolution of T_(1) precipitates in an aged Al-Cu-Li-Mg-Ag alloy 被引量:1
15
作者 Xinyue Zhao Juan Ding +2 位作者 Daihong Xiao Lanping Huang Wensheng Liu 《Journal of Materials Science & Technology》 2025年第6期139-148,共10页
The T_(1)(Al_(2) CuLi)phase is one of the most effective strengthening nanoscale-precipitate in Al-Cu alloys with Li.However,its formation and evolution still need to be further clarified during aging due to the compl... The T_(1)(Al_(2) CuLi)phase is one of the most effective strengthening nanoscale-precipitate in Al-Cu alloys with Li.However,its formation and evolution still need to be further clarified during aging due to the complex precipitation sequences.Here,a detailed investigation has been carried out on the atomic struc-tural evolution of T_(1) precipitate in an aged Al-Cu-Li-Mg-Ag alloy using state-of-the-art Cs-corrected high-angle annular dark field(HAADF)-coupled with integrated differential phase contrast(iDPC)-scanning transmission electron microscopy(STEM)and energy-dispersive X-ray spectroscopy(EDXS)techniques.An intermediate T_(1)’phase between T_(1p) and T_(1) phase,with a crystal structure and orientation rela-tionship consistent with T_(1),but exhibiting different atomic occupancy and chemical composition was found.We observed the atomic structural transformation from T_(1p) to T_(1)’phase(fcc→hcp),involving only 1/12<112>Al shear component.DFT calculation results validated our proposed structural models and the precipitation sequence.Besides,the distributions of minor solute elements(Ag,Mg,and Zn)in the pre-cipitates exhibited significant differences.These findings may contribute to a further understanding of the nucleation mechanism of T_(1) precipitate. 展开更多
关键词 PRECIPITATE Chemical composition Atomic structure Aluminium alloy STEM
原文传递
Recent developments in MQL machining of aeronautical materials:A comparative review 被引量:4
16
作者 Syed Hammad ALI Yu YAO +7 位作者 Bangfu WU Biao ZHAO Wenfeng DING Muhammad JAMIL Ahmar KHAN Asra BAIG Qi LIU Dongdong XU 《Chinese Journal of Aeronautics》 2025年第1期43-69,共27页
Minimum quantity lubrication(MQL),as a new sustainable and eco-friendly alternative cooling/lubrication technology that addresses the limitations of dry and wet machining,utilizes a small amount of lubricant or coolan... Minimum quantity lubrication(MQL),as a new sustainable and eco-friendly alternative cooling/lubrication technology that addresses the limitations of dry and wet machining,utilizes a small amount of lubricant or coolant to reduce friction,tool wear,and heat during cutting processes.MQL technique has witnessed significant developments in recent years,such as combining MQL with other sustainable techniques to achieve optimum results,using biodegradable lubricants,and innovations in nozzle designs and delivery methods.This review presents an in-depth analysis of machining characteristics(e.g.,cutting forces,temperature,tool wear,chip morphology and surface integrity,etc.)and sustainability characteristics(e.g.,energy consumption,carbon emissions,processing time,machining cost,etc.)of conventional MQL and hybrid MQL techniques like cryogenic MQL,Ranque-Hilsch vortex tube MQL,nanofluids MQL,hybrid nanofluid MQL and ultrasonic vibration assisted MQL in machining of aeronautical materials.Subsequently,the latest research and developments are analyzed and summarized in the field of MQL,and provide a detailed comparison between each technique,considering advantages,challenges,and limitations in practical implementation.In addition,this review serves as a valuable source for researchers and engineers to optimize machining processes while minimizing environmental impact and operational costs.Ultimately,the potential future aspects of MQL for research and industrial execution are discussed. 展开更多
关键词 Aerospace materials Minimum Quantity Lubrication(MQL) CRYOGENIC NANOFLUID GRINDING MILLING Sustainability
原文传递
Atomic-scale insights into microscopic mechanisms of grain boundary segregation in Al−Cu alloys 被引量:1
17
作者 Xiong SHUAI Hong MAO +2 位作者 Sai TANG Yi KONG Yong DU 《Transactions of Nonferrous Metals Society of China》 2025年第1期1-12,共12页
This study aims to clarify the mechanisms for the grain boundary(GB)segregation through investigating the absorption of excess solute atoms at GBs in Al−Cu alloys by using the hybrid molecular dynamics/Monte Carlo sim... This study aims to clarify the mechanisms for the grain boundary(GB)segregation through investigating the absorption of excess solute atoms at GBs in Al−Cu alloys by using the hybrid molecular dynamics/Monte Carlo simulations.Two segregation mechanisms,substitutional and interstitial mechanisms,are observed.The intergranular defects,including dislocations,steps and vacancies,and the intervals in structural units are conductive to the prevalence of interstitial mechanism.And substitutional mechanism is favored by the highly ordered twin GBs.Furthermore,the two mechanisms affect the GB structure differently.It is quantified that interstitial mechanism is less destructive to GB structure than substitutional one,and often leads to a segregation level being up to about 6 times higher than the latter.These findings contribute to atomic scale insights into the microscopic mechanisms about how solute atoms are absorbed by GB structures,and clarify the correlation among intergranular structures,segregation mechanisms and kinetics. 展开更多
关键词 grain boundaries segregation Al−Cu alloy intergranular structure molecular dynamics simulation Monte Carlo simulation
在线阅读 下载PDF
Performance and electromagnetic mechanism of radar-and infraredcompatible stealth materials based on photonic crystals 被引量:3
18
作者 Yanming Liu Xuan Yang +3 位作者 Lixin Xuan Weiwei Men Xiao Wu Yuping Duan 《International Journal of Minerals,Metallurgy and Materials》 2025年第3期710-717,共8页
Traditional stealth materials do not fulfill the requirements of high absorption for radar waves and low emissivity for infrared waves.Furthermore,they can be detected by various technologies,considerably threatening ... Traditional stealth materials do not fulfill the requirements of high absorption for radar waves and low emissivity for infrared waves.Furthermore,they can be detected by various technologies,considerably threatening weapon safety.Therefore,a stealth material compatible with radar and infrared was designed based on the photonic bandgap characteristics of photonic crystals.The radar stealth lay-er(bottom layer)is a composite of carbonyl iron/silicon dioxide/epoxy resin,and the infrared stealth layer(top layer)is a 1D photonic crystal with alternately and periodically stacked germanium and silicon nitride.Through composition optimization and structural adjust-ment,the effective absorption bandwidth of the compatible stealth material with a reflection loss of less than-10 dB has reached 4.95 GHz.The average infrared emissivity of the proposed design is 0.1063,indicating good stealth performance.The theoretical analysis proves that photonic crystals with this structural design can produce infrared waves within the photonic bandgap,achieving high radar wave transmittance and low infrared emissivity.Infrared stealth is achieved without affecting the absorption performance of the radar stealth layer,and the conflict between radar and infrared stealth performance is resolved.This work aims to promote the application of photonic crystals in compatible stealth materials and the development of stealth technology and to provide a design and theoretical found-ation for related experiments and research. 展开更多
关键词 microwave absorption infrared stealth photonic crystal compatible stealth
在线阅读 下载PDF
Boundary fluid constraints during electrochemical jet machining of large size emerging titanium alloy aerospace parts in gas–liquid flows:Experimental and numerical simulation 被引量:1
19
作者 Yang LIU Ningsong QU +1 位作者 Hansong LI Zhaoyang ZHANG 《Chinese Journal of Aeronautics》 2025年第1期115-130,共16页
Large size titanium alloy parts are widely used in aerospace.However,they are difficult to manufacture using mechanical cutting technology because of severe tool wear.Electrochemical jet machining is a promising techn... Large size titanium alloy parts are widely used in aerospace.However,they are difficult to manufacture using mechanical cutting technology because of severe tool wear.Electrochemical jet machining is a promising technology to achieve high efficiency,because it has high machining flexibility and no machining tool wear.However,reports on the macro electrochemical jet machining of large size titanium alloy parts are very scarce,because it is difficult to achieve effective constraint of the flow field in macro electrochemical jet machining.In addition,titanium alloy is very sensitive to fluctuation of the flow field,and a turbulent flow field would lead to serious stray corrosion.This paper reports a series of investigations of the electrochemical jet machining of titanium alloy parts.Based on the flow analysis and experiments,the machining flow field was effectively constrained.TB6 titanium alloy part with a perimeter of one meter was machined.The machined surface was smooth with no obvious machining defects.The machining process was particularly stable with no obvious spark discharge.The research provides a reference for the application of electrochemical jet machining technology to achieve large allowance material removal in the machining of large titanium alloy parts. 展开更多
关键词 Electrochemical jet machining Titanium alloys Large size parts Flow simulation Turbulent flow
原文传递
Establishment of an efficient Agrobacterium rhizogenes-mediated hairy root transformation method for subtropical fruit trees 被引量:1
20
作者 Mao Yin Yonghua Jiang +4 位作者 Yingjie Wen Fachao Shi Hua Huang Qian Yan Hailun Liu 《Horticultural Plant Journal》 2025年第4期1699-1702,共4页
Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herb... Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herbaceous plants,with notable applications in species such as Arabidopsis(Yin et al.,2024),soybean(Zhang et al.,2024),rice(Zhang et al.,2020),and Chinese cabbage(Li et al.,2021).However,its application in fruit trees is limited.This is primarily due to their long growth cycles and lack of rapid,efficient,and stable transgenic systems,which severely hinders foundational research involving plant genetic transformation(Mei et al.,2024).Furthermore,for subtropical fruit trees,the presence of recalcitrant seeds adds an extra layer of difficulty to genetic transformation(Umarani et al.,2015),as most methods rely on seed germination as a basis for transformation. 展开更多
关键词 study gene function krenek plant genetic engineering hairy root transformation fruit trees agrobacterium rhizogenes subtropical fruit trees genetic transformation chinese cabbage li
在线阅读 下载PDF
上一页 1 2 73 下一页 到第
使用帮助 返回顶部