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International Journal of minerals,metallurgy and materials 2015年第7期22卷 748-754页

作者： Zohreh yazdani Fathallah Karimzadeh mohammad-Hasan Abbasi Abbas Amini Department of materials Engineering Isfahan University of Technology

The present study characterized NbSi2-Al2O3 nanocomposite powders plasma-sprayed on Ti-6Al-4Vsubstrates. The powders were agglomerated to obtain suitable particle sizes for spraying. The agglomerated powders were then plasma-sprayed using atmospheric plasma spraying. The structural transformations of the powders along with the morphological and mechanical changes of the coatings were examined by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, and hard- ness testing. The results showed that after plasma spraying, the grain size increased, and the lattice strain decreased. However, the grain size of this compound after spraying was still in the nanometer range. The coating was uniform and exhibited good adhesion to the substrate. The microhardness and fracture toughness of the nanocomposite coating were higher than those of a nanostructured NbSi2 coating.

关键词： nanocomposites coatings plasma spraying mechanical alloying

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.gHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(Fgm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the Fgm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of Fgm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in Fgm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Effect of loading direction on interaction of two pre-existing open and closed flaws in a rock-like brittle material

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Underground Space 2020年第3期5卷 242-257页

作者： mahtab Alitalesh mahmoud yazdani Ahmadali Fakhimi marjan Naeimabadi School of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran Department of mineral Engineering New Mexico TechSocorroNMUSA

Investigations of the growth,interaction,and coalescence of cracks are important because they help to provide tools for the more realistic modeling of rock masses containing low persistence discontinuities and better estimations of the strength and stiffness of a rock *** the coalescence mechanism is useful for justifying the mechanism of continental crustal deformation,evaluating the structural failure of slopes with rock bridges,and analyzing the stability of tunnels when a mode I or mix mode failure mechanism is *** evaluation of crack growth can provide valuable information about the mechanism for the formation of new geological structures,and the formation,evolution,and growth of *** paper reports the results of diametrical compression tests on rocklike disk-shaped *** specimen contained two pre-existing open or closed *** growth,interaction,and coalescence of the pre-existing flaws were investigated both physically and numerically.A hybrid bonded particle-finite element system was used in the numerical *** results of the physical and numerical studies were in good *** particular,the induced crack patterns showed close agreement in the physical and numerical *** microscope image processing was used in the physical tests to study the dislocations along the initial *** was shown that wing crack formation was responsible for the failure of the specimen when flaws were inclined with respect to the loading *** crack growth and linkage were shown to be affected by the friction between faces of the *** addition,the slip distributions at the flaws surfaces were illustrated and examined to understand the crack propagation *** effects of the flaws on the disk failure loads were assessed both numerically and experimentally as well.

关键词： Pre-existing flaws Brazilian disk Fracture mechanics Crack propagation Coalescence Bonded particle simulation

Case study of a driven pile foundation in diatomaceous soil.I:Site characterization and engineering properties

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Journal of Rock mechanics and geotechnical Engineering 2021年第2期13卷 431-445页

作者： Jiayao Wang Ehsan yazdani T.matthew Evans School of Civil and Construction Engineering Oregon State UniversityCorvallisOR97331USA

Diatomaceous soils are comprised of the silica frustules of diatom microalgae that are present in marine and lacustrine environments throughout the *** to their unique origin,diatomaceous soils are typically characterized by high intraparticle porosity,complex particle shapes,and uniform mineralogy,causing them to exhibit atypical physical and engineering behaviors.A substantial deposit of diatomaceous silt was observed during site exploration for construction of the Buck Creek Bridge on OR140 near Klamath Falls,OR,USA.A comprehensive laboratory and in situ testing program indicated that the diatomaceous soil possessed“non-textbook”engineering ***,tested samples had high liquid limits(≈100%-140%)with natural water contents at or near the liquid ***,the soil is expected to be normally consolidated,yet high apparent overconsolidation ratios(OCR)(≈15-40)were observed both in oedometric consolidation tests and through cone penetration test(CPT)*** penetration test(SPT)results show a corrected standard penetration resistance consistent with a medium-dense sand(i.e.(N1)_(60)≈25).CPT results include corrected tip resistances(qt)of approximately 7-10 mPa and excess pore pressures(u_(2))of up to 4 *** CPT dissipation tests,pore water pressures(PWPs)returned to hydrostatic pressure in less than 1 *** this work,we synthesize these seemingly disparate material properties in an attempt to infer appropriate engineering properties for the diatomaceous deposit at the Buck Creek Bridge and attempt to provide insight into the underlying reasons for the observed behavior.

关键词： Diatomaceous soil Problematic soil Site characterization Laboratory testing

manufacturing of cast A356 matrix composite reinforced with nano- to micrometer-sized SiC particles

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Rare metals 2017年第1期36卷 46-54页

作者： Reza Taherzadeh mousavian Rasoul Azari Khosroshahi Sasan yazdani Dermot Brabazon Faculty of materials Engineering Sahand University of Technology Tabriz 65175-4171 Iran Advanced Processing Technology Research Centre School of Mechanical and Manufacturing Engineering Dublin City University Dublin 9 Ireland

In this study, large micron-sized Si C particles were fragmented via ball-milling process in the presence of iron and nickel powders, separately, to fabricate composite powders of Fe–Si C and Ni–Si C. Continuous fracturing of brittle Si C powders leads to the formation of multi-modalsized Si C powders with size of from 50 nm to slightly higher than 10 lm after 36-h ball milling. The milled powders were then incorporated into the semisolid melt of A356 aluminum alloy to ease the incorporation of fine Si C particles by using iron and nickel as their carrier *** final as-cast composites were then extruded at 500 °C with a reduction ratio of 9:1. Lower-sized composite powders with slight agglomeration are obtained for the36-h milled Ni–Si C mixture compared to that of Fe–Si C powders, leading to incorporation of Si C particles into the melt with a lower size and suitable distribution for the Ni–Si C mixture. It is found that lower-sized composite particles could release the fine Si C particles into the melt more easily, while large agglomerated composite particles almost remain in its initial form, resulting in sites of stress concentration and low-strength aluminum matrix composites. Ultimate tensile strength(UTS) and yield strength(YS) values of 243 and 135 mPa, respectively, are obtained for the aluminum matrix composite in which nickel acts as the carrier of fine ceramic particles.

关键词： Aluminum matrix composite Semisolid casting Extrusion Ni Fe

modeling metallurgical responses of coal Tri-Flo separators by a novel BNN:a"Conscious-Lab"development

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International Journal of Coal Science & Technology 2021年第6期8卷 1436-1446页

作者： mehdi Alidokht Samaneh yazdani Esmaeil Hadavandi Saeed Chehreh Chelgani Tabas Parvardeh Coal Company(TPCCO) BirjandIran Department of Electrical and Computer Engineering Islamic Azad UniversityNorth Tehran BranchTehranIran Department of Industrial Engineering Birjand University of TechnologyBirjandIran minerals and metallurgical Engineering Department of CivilEnvironmental and Natural Resources EngineeringLulea University of Technology97187 LuleaSweden

Tri-flo cyclone,as a dense-medium separation device,is one of the most typical environmentally friendly industrial techniques in the coal washery ***,no detailed investigation has been conducted to explore the effectiveness of tri-flo cyclone operating parameters on their representative metallurgical responses(yield and recovery).To fill this gap,this work for the first time in the coal processing sector is going to introduce a type of advanced intelligent method(boosted-neural network"BNN")which is able to linearly and nonlinearly assess multivariable correlations among all variables,rank them based on their effectiveness and model their produced *** assessments and modeling were considered a new concept called"Conscious Laboratory(CL)".CL can markedly decrease the number of laboratory experiments,reduce cost,save time,remove scaling up risks,expand maintaining processes,and significantly improve our knowledge about the modeled *** this study,a robust monitoring database from the Tabas coal plant was prepared to cover various conditions for building a CL for coal tri-flo ***-known machine learning methods,random forest,and support vector regression were developed to validate BNN *** comparisons indicated the accuracy and strength of BNN over the examined traditional modeling *** a sentence,generating a novel BNN within the CL concept can apply in various energy and coal processing areas,fill gaps in our knowledge about possible interactions,and open a new window for plants’fully automotive process.

关键词： Conscious laboratory BNN Tri-flo Random forest Support vector regression

Anodizing of 2024-T3 aluminum alloy in sulfuric-boric-phosphoric acids and its corrosion behavior

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Transactions of Nonferrous metals Society of China 2013年第9期23卷 2551-2559页

作者： m. SAEEDIKHANI m. JAVIDI A. yazdani Department of materials science and Engineering School of Engineering Shiraz University

The corrosion resistance of 2024-T3 aluminum alloy was improved by anodizing treatment in a mixed electrolyte containing 10% sulfuric acid, 5% boric acid and 2% phosphoric acid. Electrochemical impedance spectroscopy （EIS） technique was used to study the corrosion behavior of the anodized alloy. Using Tafel plot and salt spray techniques, it is revealed that the anodizing treatment of 2024-T3 aluminum alloy in sulfuric-boric-phosphoric acids provides better corrosion resistance and durability in comparison with the anodizing treatment in phosphoric acid or sulfuric-boric acids. This electrolyte can be a suitable alternative for chromate baths which are generally used in the anodizing of aluminum alloys.

关键词： anodizing 2024-T3 aluminum alloy mixed electrolyte EIS

Effect of shot peening process on fatigue behavior of an alloyed austempered ductile iron

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China Foundry 2011年第3期8卷 325-330页

作者： Amir Sadighzadeh Benam Sasan yazdani Behzad Avishan Faculty of materials Engineering Sahand University of Technology

Shot peening is one of the most common surface treatments to improve the fatigue behavior of metallic parts. In this study the effect of shot peening process on the fatigue behavior of an alloyed austempered ductile iron (ADI) has been studied. Austempering heat treatment consisted of austenitizing at 875℃ for 90 min followed by austempering at three different temperatures of 320, 365 and 400℃. Rotating-bending fatigue test was carried out on samples after shot peening by 0.4-0.6 mm shots. XRD and SEm analysis, micro hardness and roughness tests were carried out to study the fatigue behavior of the samples. Results indicate that the fatigue strengths of samples austempered at 320, 365 and 400℃ are increased by 27.3%, 33.3% and 48.4%, respectively, after shot peening process.

关键词： austempered ductile iron shot peening fatigue strength roughness

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity