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HIgH-TEMPERATURE LOW-CYCLE FATIgUE BEHAVIOR OF NICKEL-BASED SUPERALLOY gH4049

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Acta Metallurgica Sinica(English Letters) 1999年第1期12卷 12-15页

作者： Chen, L.J. Yao, g. wang, z.g. Tian, J.F. Inst of Metal Research The Chinese Acad of Sciences Shenyang China

The cyclic stress response and lowcycle fatigue life for wrought nickelbased superalloy gH4049 were investigated in the temperature range from 500 to 800 The relationship between the strain amplitude and the number of stress reversals was given. The behavior of cyclic hardening was observed for higher strain amplitudes at all testing temperatures and the lowcycle fatigue life generally decreased with increasing testing temperature for the same strain range. In addition, fracture surfaces of the fatigued samples were examined by using a scanning electron microscope.

关键词： superalloy low cycle fatigue fatigue life

A Model of Supernova/gamma-Ray Burst Connection Related with Strange Stars

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A Model of Supernova/Gamma-Ray Burst Connection Related with...

Effects of Current Stressing on Shear Properties of Sn-3.8Ag-0.7Cu Solder Joints

CCAST“核天体物理”研讨会

作者： X.Y. wang, z.g. Dai , T. LuDepartment of Astronomy, Nanjing University, Nanjing, 210093, ChinaCCAST (World Laboratory), P.O.Box. 8730, Beijing, 100080, ChinaLCRHEA, IHEP, CAS, Beijing, China

We here present a natural explanation of the puzzling connection between supernova and gamma-ray burst. An asymmetric supernova explosion produces a mildly relativistic jet and leaves a preferred baryon-free funnel for the fireball formed few days later by the conversion of the newborn neutron star to a strange star, or/and from the differentially rotating strange star. The fireball can be accelerated to ultra-relativistic velocity (Γ>100) due to the very low baryon contamination of the strange stax and subsequently produce the γ-ray burst. Most of the conversion energy will finally turn into the kinetic energy of the supernova ejecta, leading to a very luminous supernova similar to SN1998bw.

关键词： gamma-ray bursts - supernova general - stars neutron -elementary particles

来源： cnki会议评论

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Journal of Materials Science & Technology 2010年第8期26卷 737-742页

作者： X.J. wang Q.L. zeng Q.S. zhu z.g. wang J.K. Shang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign Urbana IL 61801 USA

Effects of electromigration on microstructure, shear strength, and fracture behavior of solder joints were investigated by single-ball shear samples of eutectic Sn-3.8Ag-0.7Cu （SAC） joined by Cu plates at two sides. The electromigration tests were conducted at a current density of about 1.1×10^3 A/cm2 and a working temperature of about 83℃. The results showed that the shear strength and flow stress decreased greatly after current stressing. Such a decrease was associated with no significant loss of the fracture strain at short electromigration but a great reduction in the fracture strain after long-term current stressing. The variation of the fracture strain with the electromigration time was shown to result from the shift of the fracture surface from the center of the solder towards the intermetallic compound （IMC） interface at the cathode.

关键词： Strength Fracture strain Voids Solder

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(gWs) within the standard model of particle physics. If these background gWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： Xinyuan wang Fan zhang Xingyu zhou Qian wang Changyu Liu Yangyang Liu Hui wang Xiaojie Liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

陇东黄土高原区人工刺槐林树干液流数据集(2017–2019)

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全球变化数据学报（中英文） 2020年第1期4卷 60-67,60-67页

作者：张军邸利陈徵尼王安民倪帆任艺彬费俊娥吴贤忠王正安韩芬汝海丽景贯阳甘肃农业大学资源与环境学院兰州730070 甘肃省林业科学研究院兰州730000 平凉市水土保持科学研究所平凉744000 陇东学院农林科技学院庆阳745000 兰州城市学院兰州730070 宁夏农林科学院固原分院固原756000

依托国家自然基金项目(41461112,31660235),在陇东黄土高原中沟小流域(35°19’N–35°20’N,107°30’E–107°31’E),选取20世纪70年代中后期大面积种植的人工刺槐林植被,根据热平衡原理,采用热扩散探针技术对所选样树的树干液流进行... 详细信息

依托国家自然基金项目(41461112,31660235),在陇东黄土高原中沟小流域(35°19’N–35°20’N,107°30’E–107°31’E),选取20世纪70年代中后期大面积种植的人工刺槐林植被,根据热平衡原理,采用热扩散探针技术对所选样树的树干液流进行持续监测,并同时测定气象因子。该数据集包括:2017年5月19日–2019年12月10日陇东黄土高原中沟小流域常规样地树干液流监测数据(数据监测频率为10分钟),数据的存储形式为:.xlsx格式,压缩后数据量为6,59KB。该数据集部分数据(2017年生长季树干液流数据)的分析研究成果(甘肃泾川中沟小流域刺槐生长盛期树干液流动态分析与陇东黄土高原区人工刺槐林树干液流特征研究)已完成。

关键词：树干液流监测数据人工刺槐林陇东黄土高原

EFFECT OF STRUCTURAL PARAMETERS ON THE THERMAL STRESS OF A NiFe_(2)O_(4)-BASED CERMET INERT ANODE IN ALUMINUM ELECTROLYSIS

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Acta Metallurgica Sinica(English Letters) 2007年第2期20卷 139-147页

作者： J. Li z.g. wang Y.Q. Lai Y.Y. Wu S.L. Ye School of Metallurgy Science and Engineering Central South University Changsha 410083 China

Inert anode has been a hot issue in the aluminum industry for many decades. With the help of FEA （finite element analysis） software ANSYS, a model was developed to simulate the thermal stress distribution working condition of an inert anode. To reduce its thermal stress, the effect of some parameters on the thermal stress distribution was investigated, including the anode height, the anode radius, the hole depth, the hole radius, and the radius of inner chamfer and outer chamfer. The results showed that in the actual working condition of an inert anode, there existed a large axial tensile stress near the tangent interface between the anode and bath, which was the major cause of anode breaking. Increasing the anode height and reducing the hole depth properly seemed to be beneficial for the stress distribution. With the increase of anode radius, the stress distribution became better first and then deteriorated, the reasonable value was between 0.045 to 0.06m. The hole radius had a significant effect on the stress and a smaller radius would reduce the thermal stress. The effect of the radius of the inner chamfer and the outer chamfer was less than other parameters.

关键词： inert anode thermal stress structural parameter aluminum electrolysis

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

A High Power Conversion Efficiency L-Band Erbium Doped Fiber Amplifier

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光学学报 2003年第S1期23卷 383-384页

作者： z.g. Lu C.P. grover Institute for National Measurement Standards National Research Council M-50 1200 Montreal Road Ottawa ON K1 A OR6 CanadaInstitute for National Measurement Standards National Research Council M-50 1200 Montreal Road Ottawa ON K1 A OR6 Canada

By using two sections of erbium doped fiber and a fiber optical reflector, a novel, highly efficient L-band amplifier is demonstrated with significantly power-conversion-efficiency enhancement and the gain increasing ... 详细信息

关键词： EDFA as of length high with A High Power Conversion Efficiency L-Band Erbium Doped Fiber Amplifier ASE been for

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