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焊后热处理对异种金属搅拌摩擦焊2024-T4和7075-T6铝合金接头性能的影响（英文）

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Transactions of Nonferrous metals Society of China 2018年第7期28卷 1287-1297页

作者： b.SAFARbALI m.SHAmANIAN A.ESLAmI Department of materials Engineering Isfahan University of Technology

研究焊后热处理对异种金属搅拌摩擦焊AA7075和AA2024接头性能的影响。在一定的参数下焊接后,对焊接接头进行固溶处理和不同的时效处理。采用光学显微镜、SEm、FE-SEm、XRD和EDS表征材料的显微组织和相成分,最后测试对比热处理前后样品... 详细信息

研究焊后热处理对异种金属搅拌摩擦焊AA7075和AA2024接头性能的影响。在一定的参数下焊接后,对焊接接头进行固溶处理和不同的时效处理。采用光学显微镜、SEm、FE-SEm、XRD和EDS表征材料的显微组织和相成分,最后测试对比热处理前后样品的力学性能。结果显示,与焊接后未热处理的接头相比,焊后热处理过程可以明显提高2024-T6和7075-T6焊接接头的力学性能,7075-T6的力学性能提高更明显,这是因为在时效过程中形成细小沉淀相,尽管有异常晶粒长大。未热处理的AA7075的接头断裂发生在后退侧热机械影响区(TmAZ)和高热影响区(HAZ)的界面,而热处理后断裂位置转移到接头的搅拌区(SZ)。未热处理的接头断裂为穿晶断裂,而热处理后样品的断裂主要以晶内断裂为主,这主要是因为接头热处理后晶体内的沉淀相发生分解和粗化。

关键词：搅拌摩擦焊异种金属焊接焊后热处理显微组织力学性能

Performance analysis of multiple gain boost converter with hybrid maximum power point tracker for solar PV connected to grid

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Clean Energy 2021年第4期5卷 655-672页

作者： b.m.Kiran Kumar m.S.Indira S.Nagaraja Rao m S Ramaiah University of Applied Sciences Department of Electrical EngineeringBangaloreIndia-560058

This paper analyses the performance of a multiple gain boost converter(mGbC)connected to a solar photovoltaic(SPV)system with a grid-tied inverter.The capacitor inductor capacitor(CLC)-based mGbC is integrated to lift the output voltage of the SPV to the required level.The voltage lifts/levels in a boost converter(bC)are based on the number of CLC cells.The suggested mGbC is compared with various conventional bCs in terms of boost factor and component count.A hybrid fuzzy logic-perturb&observe maximum power point tracker(HFL-P&O mPPT)developed is used to monitor P_(max)(maximum power)generated by the SPV.Also,a comparative analysis of the suggested mPPT with a conventional P&O and fuzzy logic-based(FLb)mPPT for a CLC-based mGbC is presented.The comparison is made in terms of rise time,voltage ripples(%),steady-state time and boost factor.The output characteristics of the developed model for different irradiation conditions are analysed using the mATLAb/Simulink tool.The mPPT simulation result exhibits minimum oscillations at mPP and a significantly better rise time of 0.015 s when compared with a conventional mPPT and FLb mPPT.The proposed CLC-mGbC gives an appreciable boost factor of 4.The generated SPV power is supplied to the grid through a conventional inverter and synchronized using a phase-locked loop system.The total harmonic distortion of 1.66%obtained in the output current of the inverter is within the permissible range of the IEEE standards.

关键词： CLC-mGbC FLb mPPT Grid-tie inverter SPV THD

Topological transverse thermoelectrics:A new way forward?

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The Innovation 2023年第6期4卷 23-24页

作者： Shubham Yadav b.m.Anil Kumar Satya N.Guin Department of Chemistry Birla Institute of Technology and SciencePilani-Hyderabad CampusHyderabad 500078India

Electronic structure is one of the most fundamental factors that decide the physical properties of a material.In the past 18 years,a deeper fundamental understanding of the electronic band structure of material has resulted in the development of topological band theory,which has reclassified solid-state materials into two different classes:topologically trivial and topologically nontrivial.Topologically nontrivial systems provide a new opportunity for material design for fundamental and functional applications from experimental and theoretical viewpoints.

关键词： material. topological nontrivial

Tie-line Power Flow Control method for Gridconnected microgrids with SmES based on Optimization and Fuzzy Logic

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Journal of modern Power Systems and Clean Energy 2020年第5期8卷 941-950页

作者： Sayed m.Said Abdelfatah Ali bálint Hartmann Department of Electrical Engineering Aswan University81542 AswanEgypt Department of Electric Power Engineering Budapest University of Technology and Economics1111 BudapestHungary Department of Electrical Engineering South Valley University83523 QenaEgypt

In an active distribution grid,renewable energy sources(RESs)such as photovoltaic(PV)and energy storage systems(e.g.,superconducting magnetic energy storage(SmES))can be combined with consumers to compose a microgrid(mG).The high penetration of PV causes high fluctuations of tie-line power flow and highly affects power system operations.This can lead to several technical problems such as voltage fluctuations and excessive power losses.In this paper,a fuzzy logic control based SmES method(FSm)and an optimized fuzzy logic control based SmES method(OFSm)are proposed for minimizing the tie-line power flow.Consequently,the fluctuations and transmission power losses are decreased.In FSm,SmES is used with a robust fuzzy logic controller(FLC)for controlling the tie-line power flow.An optimization model is employed in OFSm to simultaneously optimize the input parameters of the FLC and the reactive power of the voltage source converter(VSC)of SmES.The objective function of minimizing the tieline power flow is incorporated into the optimization model.Particle swarm optimization(PSO)algorithm is utilized to solve the optimization problem while the constraints of the utility power grid,VSC,and SmES are considered.The simulation results demonstrate the effectiveness and robustness of the proposed methods.

关键词： Utility power grid microgrid photovoltaic(PV) superconducting magnetic energy storage(SmES) tie-line power fuzzy logic control(FLC)

Hybrid reinforced thermoset polymer composite in energy absorption tube application:A review

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Defence Technology（防务技术） 2018年第4期14卷 291-305页

作者： A.b.m.Supian S.m.Sapuan m.Y.m.Zuhri E.S.Zainudin H.H.Ya Department of mechanical and manufacturing Engineering Universiti Putra Malaysia Laboratory of bio Composite Technology Institute of Tropical Forestry and Research Products (INTROP)Universiti Putra Malaysia Department of mechanical Engineering Universiti Teknologi Petronas

The custom of hybridization fibre composite in energy absorption tube application has gained the attention of structural crashworthiness in composite material industry. Thus, the approach of this review is to understand the effect in hybridization within metal/synthetic fibre composite, synthetic/synthetic fibre composite and nature/synthetic fibre composite as energy absorption tube, which reflects on the energy absorption characteristics and crashworthiness behaviors in previous the study. by way of instance, a wide range of methodology and particular parameter in previous study such as the effect in fibre arrangement, matrix polymer, technique of fabrication, fibre treatment(natural fibre), design in geometry/cross-section and others mechanism of hybrid fibre composite tube are highlighted which to comprehend the capability of the mechanical performance and collapsible behavior as sacrificial structure in high-performance structure applications. moreover, in the recently studies there have been many of the research regarding structural materials as energy absorption tube has been introduced such as metal/matrix composites, new alloy metals and polymer composites which intended to evaluate the performance of these materials into circumstance in loading and impact characteristic. Therefore, this review article is trying to explore the research articles related to the effect of hybridization fibres and thermoset polymer as reinforcement for energy absorption tube research and expected would provide an information and idea which to expend the knowledge in future study of hybridization effect for energy absorption tube, moreover the development for future potential as new hybrid composite fibre materials from the natural/synthetic fibres reinforced composite material in employing of high-performance energy absorption tube application is still less discover and highlighted.

关键词： Energy absorption tube Hybrid composites Collapse behavior Crashworthiness

Construction strategies for a NATm tunnel in Sao Paulo, brazil, in residual soil

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Underground Space 2022年第1期7卷 1-18页

作者： Osvaldo P.m.Vitali Tarcisio b.Celestino Antonio bobet Lyles School of Civil Engineering Purdue UniversityWest LafayetteIN 47907USA Sao Carlos School of Engineering University of Sao PauloSao CarlosSP 13566Brazil

Due to the fast growth of urban areas worldwide,the demand for tunnels in developed areas is increasing.The design and construc-tion of those tunnels are complex because of their shallow depths and their interaction with existing aboveground and buried structures,which results in rather limited allowable ground deformations induced by the tunnel excavation and support.In tropical regions,residual porous soils near the surface are common.Those soils are highly deformable;thus,tunneling may induce large ground deformations that may damage nearby structures.The new Austrian tunneling method(NATm)and the sprayed concrete lining(SCL)technique are being widely employed in several big cities in tropical regions,but little research has been conducted to assess the induced ground deformations in residual soils,common in tropical areas.This paper provides insight into this issue.A well-documented metro tunnel in Sa˜o Paulo,brazil,in a residual red porous clay,was analyzed using 3D finite element method(FEm).The behavior of the residual red porous clay was approximated by an advanced constitutive soil model calibrated with triaxial tests on intact samples extracted at the site.Predictions of the tunnel deformations during construction matched the field data.The calibrated model was then used to explore the tunnel per-formance under different construction strategies.The influence of partial face excavation,unsupported span length,support stiffness and pipe roof umbrella were assessed.The numerical results showed that partial face excavation was effective to reduce ground deformations ahead of the face of the tunnel and to improve face stability;however,the settlements behind the face increased because of the delay in closing the primary lining.The installation of a stiffer liner closer to the face reduced the ground deformations significantly.The pipe roof umbrella was the most effective technique to reduce the ground deformations around the tunnel;however,the numerical results did not consider deformations that could be ind

关键词： Tunnel NATm Residual soil FEm 3D face effects Ground deformation Face stability

Gene set enrichment analysis of alpha-glucosidase inhibitors from Ficus benghalensis

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Asian Pacific Journal of Tropical biomedicine 2019年第6期9卷 263-270页

作者： Pukar Khanal b.m.Patil Department of Pharmacology and Toxicology KLE College of Pharmacy Belagavi KLE Academy of Higher Education and Research (KAHER)

Objective:To identify alpha-glucosidase inhibitors from Ficus benghalensis and analyze gene set enrichment of regulated protein molecules.methods:The phytoconstituents of Ficu.s benghalen.sis were queried for inhibitors of alphaglucosidase,also identified as aldose reductase inhibitors.Druglikeness score,absorption,distribution,metabolism,excretion and toxicity profile,biological spectrum,and gene expression were predicated for each compound.Docking study was performed to predict the binding affinity with alpha-glucosidase and aldose reductase and compared with clinically proven molecules.Kyoto Encyclopedia of Genes and Genomes pathway analysis was performed for the regulated genes to identify the modulated pathways.Results:Apigenin,3,4’,5,7-tetrahydroxy-3’-methoxyflavone,and kaempferol were identified as inhibitors of alpha-glucosidase and aldose reductase.Kaempferol was predicted to possess the highest binding affinity with both targets.The p53 signaling pathway was predicted to modulate the majority of protein molecules in diabetes mellitus.All the alpha-glucosidase inhibitors were also predicted as membrane integrity agonist and anti-mutagenic compounds.Conclusions:The current study indicates alpha-glucosidase inhibitors from Ficus benghale,nsis can act as aldose reductase inhibitors after absorption from the intestinal tract.Furthermore,these phytoconstituents are involved in the regulation of numerous protein molecules and pathways.Hence,the anti-diabetic efficacies of these compounds are due to their action on multiple protein molecules and synergistic effects which should be confirmed by future investigations.

关键词： Ficus benghalensis Gene set enrichment Kaempferol Network pharmacology Type 2 diabetes mellitus

Adult neurogenesis from reprogrammed astrocytes

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Neural Regeneration Research 2020年第6期15卷 973-979页

作者： brian b.Griffiths Anvee bhutani Creed m.Stary Department of Anesthesiology Pain & Perioperative Medicine Stanford University School of Medicine

The details of adult neurogenesis,including environmental triggers,region specificity,and species homology remain an area of intense investigation.Slowing or halting age-related cognitive dysfunction,or restoring neurons lost to disease or injury represent just a fraction of potential therapeutic applications.New neurons can derive from stem cells,pluripotent neural progenitor cells,or non-neuronal glial cells,such as astrocytes.Astrocytes must be epigenetically"reprogrammed"to become neurons,which can occur both naturally in vivo,and via artificial exogenous treatments.While neural progenitor cells are localized to a few neurogenic zones in the adult brain,astrocytes populate almost every brain structure.In this review,we will summarize recent research into neurogenesis that arises from conversion of post-mitotic astrocytes,detail the genetic and epigenetic pathways that regulate this process,and discuss the possible clinical relevance in supplementing stem-cell neurogenic therapies.

关键词： astrocyte brain dedifferentiation development disease glia injury neurogenesis

An app to assist farmers in the identification of diseases and pests of coffee leaves using deep learning

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Information Processing in Agriculture 2022年第1期9卷 38-47页

作者： Jose G.m.Esgario Pedro b.C.de Castro Lucas m.Tassis Renato A.Krohling LAbCIN-Nature Inspired Computing Federal University of Espirito SantoAv.Fernando Ferrari514CEP 29075-910 VitoriaEspırito SantoESBrazil LAbCIN-Nature Inspired Computing and PPGI-Graduate Program in Computer Scienceand Production Engineering DepartmentFederal University of Espirito SantoAv.Fernando Ferrari514CEP 29075-910 VitoriaEspırito SantoESBrazil

In recent years,deep learning methods have been introduced for segmentation and classi-fication of leaf lesions caused by pests and pathogens.Among the commonly used approaches,convolutional neural networks have provided results with high accuracy.The purpose of this work is to present an effective and practical system capable of seg-menting and classifying different types of leaf lesions and estimating the severity of stress caused by biotic agents in coffee leaves using convolutional neural networks.The proposed approach consists of two stages:a semantic segmentation stage with severity calculation and a symptom lesion classification stage.Each stage was tested separately,highlighting the positive and negative points of each one.We obtained very good results for the severity estimation,suggesting that the model can estimate severity values very close to the real values.For the biotic stress classification,the accuracy rates were greater than 97%.Due to the promising results obtained,an App for Android platform was developed and imple-mented,consisting of semantic segmentation and severity calculation,as well as symptom classification to assist both specialists and farmers to identify and quantify biotic stresses using images of coffee leaves acquired by smartphone.

关键词： Convolutional neural networks Semantic segmentation Coffee leaf Pests and diseases App.development