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Journal of materials Science & Technology 2014年第12期30卷 1284-1288页

作者： B.zhang z.m.song L.m.Lei L.Kang G.P.zhang Key Laboratory for Anisotropy and Texture of materials Ministry of Education Northeastern University Shenyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of Sciences AVIC Commercial Aircraft Engine Co. Ltd.

Fatigue properties of the Ti-6.5Al-3.5mo-1.5zr-0.3Si alloy sheets containing different numbers of α/β Widmansttten colonies in the thickness direction of the sheets were investigated by tensionetension fatigue testing. It is found that fatigue properties of the Ti alloy either in low- or high-stress amplitude regimes become more sensitive to the sheet thickness of the Ti alloy as the sheet thickness is comparable to the length scale of the Widmansttten colonies. The basic mechanism of such length scale-sensitive fatigue properties in the Ti alloy was elucidated.

关键词： Fatigue Ti alloy microstructure Size effect

microstructural Evolution and Service Performance of Cold-drawn Pure Aluminum Conductor Wires

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Journal of materials Science & Technology 2017年第9期33卷 1039-1043页

作者： X.m.Luo z.m.song m.L.Li Q.Wang G.P.zhang Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences

microstructures and service performance(mechanical and electrical properties) of the commercially pure Al conductor wires subjected to different cold drawing strains were investigated. The results show that the microstructures of the cold-drawn Al wires along the radial direction were inhomogeneous, i.e. the texture in the center region was strong and weak components, while that in the surface region shifted from the initial cubic texture to a component and finally developed into a strong component. The volume fraction of the high angle grain boundaries in the surface region was higher than that in the center region. The cold-drawing process greatly enhanced the yield strength of the pure Al wires while retained the acceptable electrical resistivity. The strengthening mechanism and the variation of electrical conductivity of the cold-drawn Al wires are discussed through correlating with microstructure evolution.

关键词： Cold drawing Aluminum microstructure Strength Conductivity

On Temperature and Strain Rate Dependent Strain Localization Behavior in Ti-6.5Al-3.5mo-1.5zr-0.3Si Alloy

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Journal of materials Science & Technology 2013年第3期29卷 273-278页

作者： B.zhang L.m.Lei X.L.Jiang z.m.song X.Huang G.P.zhang Key Laboratory for Anisotropy and Texture of materials(ministry of Education) Northeastern University Titanium Alloys Laboratory Beijing Institute of Aeronautical Materials AVIC commercial Aircraft Engine Co. Ltd. Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences

Deformation behaviors of Ti-6.5Al-3.5mo-1.5zr-0.3Si alloys with α/β lamellar structure were investigated systematically at different temperatures from room temperature to 950 ~C and different strain rates. Results reveal that when the deformation temperature is higher than a critical temperature of 600℃, an evident transition of deformation behavior from localized shear banding to α/β lamella kinking, flow softening and temperature/strain rate-dependent peak flow stress occurred in the alloy. The critical conditions for the occurrence of internal cracking and strain localization behavior associated with temperature and strain rate were determined.

关键词： Titanium alloy Hot working Temperature Strain rate Shear band

Toward developing Ti alloys with high fatigue crack growth resistance by additive manufacturing

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Journal of materials Science & Technology 2023年第1期132卷 166-178页

作者： F.Wang L.m.Lei X.Fu L.Shi X.m.Luo z.m.song G.P.zhang Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China AECC Commercial Aircraft Engine Co. Ltd.Shanghai 201306China

Fatigue crack growth behaviors were investigated by three-point bending tests for TA19 alloy fabricated by laser metal deposition and four kinds of heat-treated *** crack growth resistance of the TA19 samples in the near-threshold regime and Paris regime was evaluated through the experimental characterization and theoretical analysis of the interaction between fatigue crack andα/βphase inter-face,columnar prior-βgrain boundary and colony *** results show that in the near-threshold regime,the fatigue crack propagation threshold and resistance increase with the increase of widths of lamellarαp phases and colonies,and the decrease of the number ofαlaths with an angle(ϕ)relative to the applied stress direction ranging from 75°to 90°.In the Paris regime,the fatigue cracking path can be deflected at colony boundaries or columnar prior-βgrain *** larger the deflection angle,the more tortuous the cracking path and the lower the fatigue crack growth *** angle(γ)of the columnar prior-βgrain growth direction relative to the build direction affects not onlyϕof differentαvariants,but also the fatigue cracking path deflection angle(θij)at columnar prior-βgrain *** optimal combination ofγ=0°-15°-0°-15°for several adjacent columnar prior-βgrains is derived from the theoretical analysis,and that can effectively avoidϕbeing in the range from 75°to 90°and makeθij as large as *** findings provide a guide for the selection of scanning strategies and process parameters to additively manufacture Ti alloys with high fatigue damage tolerance.

关键词： Ti alloy Fatigue crack growth Additive manufacturing Phase interface Grain boundary

用于确定速度和衰减的2.5D全波井间反演法

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石油物探译丛 1994年第3期 70-72页

作者： z.m.song 徐仪征

在不同的二维问题(例如2.5维结构)情况中,song和Williamson(1992)曾介绍过一种三维震源波场的精确模拟方法。本文介绍了一种频率域波场反演法,利用此法可将Pratt(1989)的方法扩展用于2.5维。因为动力学方法是正确的,所以计算的波场在没... 详细信息

在不同的二维问题(例如2.5维结构)情况中,song和Williamson(1992)曾介绍过一种三维震源波场的精确模拟方法。本文介绍了一种频率域波场反演法,利用此法可将Pratt(1989)的方法扩展用于2.5维。因为动力学方法是正确的,所以计算的波场在没有明显的平界面变化情况下可直接与实际数据对比,并可进行非线性迭代反演。按照Tarantola(1984)的观点,反演可表述为最小二乘方最优化问题,并利用Born线性近似导出给定模型的梯度方向。本方法的潜在效率是很高的,因为每次迭代只有一个频率分量需要估算。在开始时频率应该很低,这样可避免周期跳跃效应,然后在反演时可加大频率,以便提高分辨率。在恒密度声学介质情况下,衰减可看作速度场的虚部,它很容易包括在反演中。此方法无需对频率与衰减的关系做任何假设,其潜在效率已用含断层层状模型上计算的合成数据集作了证明。该速度(即速度实部)几乎可恢复到现有频率所能达到的分辨率极限。虽然衰减恢复的精度较低,但仍然可用。

关键词：速度衰减地震波地震数据

Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.ImRAN T.ASGHAR z.ABBAS Department of mathematics Division of Science and TechnologyUniversity of Education Department of mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAm).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词：

Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： song Jiang Congwen zhu Ning Jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO

Targeting epigenetic mechanisms in amyloid-β-mediated Alzheimer’s pathophysiology:unveiling therapeutic potential

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Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie z.Li Nagendran Ramalingam Shaomin Li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alzheimer’s disease is a prominent chronic neurodegenerative condition characterized by a gradual decline in memory leading to *** evidence suggests that Alzheimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alzheimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alzheimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alzheimer’s *** suggest that addressing Alzheimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alzheimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

Generalized Dual Symmetry mechanical Performance of Nano magnetic Composite

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上海交通大学学报 2004年第Z2期38卷 48-53页

作者： Li Yong song Jian zhang z.m Department of Applied mechanics Beijing Institute of Technology Beijing100081 China State Key Laboratory of Automotive Safety And Energy Tsinghua University Beijing100084China State Key Laboratory of Automotive Safety And Energy Tsinghua University Beijing100084China Center of Solid Mechanics Beijing University of Aeronautics and AstronauticsBeijing100083China

Nano magnetic composite is a kind of heterogeneous material. Scientists found the symmetrical and dual symmetrical phenomena in its structure previously and we find the generalized dual symmetry mechanical performance in Nano magnetic Composite and further establish the theory. The applicable nano magnetic composite structure is analyzed thoroughly and systematically. Such phenomena as serration and step dispersing distribution of bending stress and mirror reflection of interlaminar stress are thus found. Therefore, starting from the physical features of materials, Nano magnetic Composite are analyzed on the basis of the understanding and application of the generalized dual symmetry mechanical performance. In addition, the design parameter is optimized to attain the goal of maximizing the use of materials, which is quite meaningful.

关键词： nano magenetic composite dual symmetrical heterogeneous model

Fecal microbiota transplantation in allergic diseases

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World Journal of methodology 2025年第2期15卷 83-91页

作者： Ece TüsüzÖnata ÖnerÖzdemir Division of Pediatric Allergy and Immunology Medical FacultySakarya UniversityAdapazarı54100SakaryaTürkiye

microorganisms such as bacteria,fungi,viruses,parasites living in the human intestine constitute the human intestinal *** refers to composi-tional and quantitative changes that negatively affect healthy gut *** recent years,with the demonstration that many diseases are associated with dysbiosis,treatment strategies targeting the correction of dysbiosis in the treat-ment of these diseases have begun to be *** microbiota trans-plantation(FmT)is the process of transferring faeces from a healthy donor to another recipient in order to restore the gut microbiota and provide a therapeutic *** studies have gained popularity after probiotic,prebiotic,symbiotic studies in the treatment of dysbiosis and related *** has emerged as a potential new therapy in the treatment of allergic diseases as it is associated with the maintenance of intestinal microbiota and immunological balance(T helper 1/T helper 2 cells)and thus suppression of allergic *** this article,the definition,application,safety and use of FmT in allergic diseases will be discussed with current data.

关键词： microbiota Dysbiosis Faecal microbiota transplantation Allergic diseases