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crack Initiation Mechanism of Z3cN20.09M Duplex Stainless Steel during corrosion fatigue in Water and Air at 290 °c

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Journal of Materials Science & Technology 2015年第11期31卷 1144-1150页

作者： H.c.Wu B.Yang Y.Z.Shi q.Gao Y.q.Wang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing collaborative Innovation center of Universal Iron & Steel Technology School of Materials Science and Engineering Anhui University of Technology

The crack initiation mechanism of a Z3cN20.09M duplex stainless steel （DSS） during corrosion fatigue （cf） in water and air at 290 ℃ was investigated by using a cf cracking machine and a scanning electron microscopy （SEM）. The cracks were initiated successively at the persistent stip bands （PSBs）, phase boundaries （PBs） and pitting corrosion points （PcPs） of the specimens when they were tested in water at 290 ℃, while in airat 290 ℃ the cracks were only initiated at the PSBs and PBs. And the cracks were found mainly to initiate at the PSBs and PBs when the specimens were tested in water and air at 290 ℃, respectively. The results also reveal that the cracks were likely to be initiated at the first 20% of fatigue life of the specimens tested in water at 290 ℃. However, the cracks were not found until 50% of fatigue life when tested in air at 290 ℃. Moreover, the crack numbers of the specimens tested in water at 290 ℃ were much more than those tested in air at 290 ℃.

关键词： Duplex stainless steel corrosion fatigue crack initiation High temperature water

Influence of fe Addition on Products of Self-Propagating High-Temperature Synthesis Reaction in 3Ti-Si-2c System

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稀有金属材料与工程 2009年第A03期38卷 113-118页

作者： Guan q L Wang H Y Li S L Si W P Jiang q c Key Laboratory of Automobile Materials of Ministry of Education Jilin University Changchun 130025 China

Influence of fe addition on products of self-propagating high-temperature synthesis (SHS) reaction in 3Ti-Si-2c system was investigated in the present study. Without fe addition, Ti5Si3 and Tic are the dominant phases along with a small amount of Ti3Sic2 phase and unreacted c left in the final products. As fe content ranges from 10% to 30%, the products consist of Tic, Ti5Si3, fe2Ti and unreacted c, but no trace of Ti3Sic2 phase is detected. furthermore, the amounts of both fe2Ti and c phases increase with fe content increasing. Addition of fe has a great effect on the reaction route and significantly restrains the formation of Ti3Sic2 during the combustion synthesis process, and therefore, the SHS is not an effective fabrication technique to synthesize the ternary Ti3Sic2 ceramic in either 3Ti-Si-2c or fe-3Ti-Si-2c system. Besides, without fe addition, Ti5Si3 presents as the coarse irregular appearance with an obviously sintered morphology. In contrast, the shape of Ti5Si3 exhibits more and more spherical (cobblestone-like) and the surface becomes increasingly smooth, because the amount of liquids formed during the SHS reaction increases with the increase of fe content. On the other hand, with fe content increasing from 0 to 30 wt.%, the particulate size of Tic decreases from more than 5 μm to 1 μm or less, mainly due to the fact that the combustion temperature decreases with the increase of fe content in the preforms.

关键词：复合材料铁含量燃烧过程物理性能

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： Md Al Raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORfBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORfBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORfBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

Modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies

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Research in Astronomy and Astrophysics 2011年第12期11卷 1429-1448页

作者： James q.feng c.f.Gallo Superconix Inc 2440 Lisbon AvenueLake ElmoMN 55042USA

We present an efficient, robust computational method for modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies. With appropriate mathematical treatments, the apparent numerical difficulties associated with singularities in computing elliptic integrals are completely removed. Using a boundary element discretization procedure, the governing equations are transformed into a linear algebra matrix equation that can be solved by straightforward Gauss elimination in one step without further iterations. The numerical code implemented according to our algorithm can accurately determine the surface mass density distribution in a disk galaxy from a measured rotation curve （or vice versa）. for a disk galaxy with a typical flat rotation curve, our modeling results show that the surface mass density monotonically decreases from the galactic center toward the periphery, according to Newtonian dynamics. In a large portion of the galaxy, the surface mass density follows an approximately exponential law of decay with respect to the galactic radial coordinate. Yet the radial scale length for the surface mass density seems to be generally larger than that of the measured brightness distribution, suggesting an increasing mass-tolight ratio with the radial distance in a disk galaxy. In a nondimensionalized form, our mathematical system contains a dimensionless parameter which we call the ＂galactic rotation number＂ that represents the gross ratio of centrifugal force and gravitational force. The value of this galactic rotation number is determined as part of the numerial solution. Through a systematic computational analysis, we have illustrated that the galactic rotation number remains within 4-10% of 1.70 for a wide variety of rotation curves. This implies that the total mass in a disk galaxy is proportional to V02 Rg, with V0 denoting the characteristic rotation velocity （such as the ＂flat＂ value in a typical ro- tation curve） and Rg the radius of the galacti

关键词： galaxy: disk -- galaxies: general -- galaxies: kinematics and dynamics -- galaxies: structure -- methods: numerical and analytical

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada faculty of Medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EMBASE,Ovid MEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

Axisymmetric wetting of a liquid droplet on a stretched elastic membrane

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Applied Mathematics and Mechanics(English Edition) 2023年第6期44卷 997-1006页

作者： c.q.RU Department of Mechanical Engineering University of AlbertaEdmontonAB T6G 2G8Canada

Wetting of a liquid droplet on another liquid substrate is governed by the well-known Neumann *** present work aims to develop an explicit modified version of the Neumann equations for axisymmetric wetting of a liquid droplet on a highly stretched elastic membrane of non-zero bending *** explicit modified form of the Neumann equations is derived to determine the two contact angles,which is reduced to Young's equation for a liquid droplet on a rigid membrane or to the Neumann equations for a liquid droplet on another liquid *** implications of the modified Neumann equations are examined by comparison with some previous results reported in the recent literature,particularly considering the ranges of material and geometrical parameters of the liquid droplet-membrane system which have not been recently addressed in the literature.

关键词： Neumann equation Young's equation liquid droplet membrane pretension

Interfacial Instability of Two Bonded Elastic Bodies Driven by Interface or Bulk Residual Stress

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Acta Mechanica Solida Sinica 2023年第6期36卷 914-920页

作者： c.q.Ru Department of Mechanical Engineering University of AlbertaEdmonton T6G 2G8Canada

Inspired by recent research interest in the interface wrinkling of bonded materials in diverse areas of 3D printing,the present work studies the interfacial instability of two bonded elastic bodies driven by negative interfacial tension or compressible bulk residual *** interfacial instability modes decaying exponentially with distance from the interface,the present model is formulated for two bonded elastic half-spaces with a planar interface under plane *** explicit expression is given for the wavenumber of interfacial instability driven by negative interfacial tension,and a critical condition is derived for interfacial instability driven by compressive bulk residual *** derived results are validated with comparison to known results on surface instability of an elastic half-space,and the role of shear modulus ratio and Poisson’s ratios of two bonded elastic bodies in interfacial instability,an issue to be addressed in literature,is studied with specific reference to material parameters used in some areas of 3D printing.

关键词： Interfacial tension Surface tension Interfacial instability 3D printing Interface wrinkling

Precipitation on stacking faults in Mg–9.8wt%Sn alloy

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Journal of Materials Science & Technology 2020年第10期42卷 230-240页

作者： c.q.Liu c.He H.W.chen J.f.Nie International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing400044China Department of Materials Science and Engineering Monash UniversityVictoria3800Australia Electron Microscopy center Chongqing UniversityChongqing400044PR China

In this work,we have systematically investigated precipitation ofβ’-Mg3Sn phase on intrinsic stacking faults I1 and I2 in a Mg-9.8 wt%Sn alloy using aberration-corrected scanning transmission electron *** observed I1 faults are generated by the dissociation of c+a perfect dislocations and bounded by frank partial dislocations having a Shockley *** ofβ’on I1 involves a shear of 1/3α,similar to its formation directly from theα-Mg ***β’phase often nucleates at one end of an I1 fault due to the interaction between shear strain fields ofβ’and the Shockley component of the frank partial at that end,and subsequently grows towards the other end of the *** theβ’reaches to the other end,the Shockley partial bounding the lengthening end of theβ’reacts with the frank partial bounding the fault,generating an a perfect dislocation that can glide away from the precipitate and the *** observed I2 faults are generated by the dissociation of a perfect dislocations and bounded by Shockley *** ofβ’on I2 does not need a shear of 1/3α,since the pre-existing I2 fault already provides an ABcA four-layer structure ofβ’.Thickening of theβ’that has already formed on the I2 involves the successive occurrence of three crystallographically equivalent shears of 1/3αon every second(0002)αplane of theα-Mg *** this thickening mechanism is similar to that of theβ’formed directly from theα-Mg matrix,an a perfect dislocation will be produced when theβ’is thickened to eight layers,and it can again glide away from the precipitate and the fault.

关键词： Heterogeneous precipitation HAADf-STEM Shockley partial dislocation frank partial dislocation Dislocation reaction

Zinc-oxide/PDMS-clad tapered fiber saturable absorber for passively mode-locked erbium-doped fiber laser

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chinese Physics B 2021年第5期30卷 384-389页

作者： f D Muhammad S A S Husin E K ng K Y Lau c A c Abdullah M A Mahdi Department of Physics Faculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Wireless and Photonics Networks Research centre Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Electronics and Nanoengineering Tietotie 3Aalto University02150 EspooFinland

We propose and demonstrate a passively mode-locked erbium-doped fiber laser(EDfL)based on zinc-oxide/polydimethylsiloxane(ZnO/PDMS)saturable absorber(SA)that evanescently interacts with the light on a tapered *** ZnO/PDMS composite is coated on the whole surface of the tapered fiber to guarantee the maximum efficiency of the SA device,with a measured insertion loss of 0.87 dB and a modulation depth of 6.4%.The proposed laser can generate soliton mode-locking operation at a threshold power of 33.07 *** generated output pulse yields a repetition rate and pulse width of 9.77 MHz and 1.03 ps,*** results indicate that the proposed ZnO/PDMS-clad tapered fiber could be useful as an efficient,compatible,and low-cost SA device for ultrafast laser applications.

关键词： zinc-oxide saturable absorber tapered fiber mode-locked fiber laser