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中国有色金属学会会刊：英文版 2001年第4期11卷 509-512页

作者：刘澄张国定 m.naka State Key Laboratory of metal matrix Composites Shanghai Jiaotong University Joining and Welding Research Institute of Osaka University Osaka 567-0047 Japan

An AFm (Atomic Force microscope) based nanoindentation method for local measurement of mechanical properties near interfaces in both angular and blunted SiC particle reinforced LD2 composites is presented. The blunted composite exhibits an improved ductility than the angular counterpart. The nanoindentation examination shows that the micromechanical properties near interfaces distribute unevenly and vary with particle shape in the SiC p/LD2 composites. There are a higher nanohardness value and a lower plastic deformation capacity around an angular particle than around a blunted one. It is inferred that the residual stress and strain concentrations are severer around the angular particle, which causes matrix cracking at a lower external strain level and leads to a lower ductility of the angular composite.

关键词： micromechanical properties nanoindentation interface ductility

Interfacial reaction and growth behavior of reaction layer of Si_3N_4/Si_3N_4 joint brazed by Cu-Zn-Ti filler alloy

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中国有色金属学会会刊：英文版 2005年第S2期15卷 261-265页

作者：张杰周玉 m.naka School of materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Joining and Welding Research Institute Osaka University Ibaraki Osaka 567-0047 Japan

Si3N4 ceramic was jointed to itself using a filler alloy of Cu-Zn-Ti by the reaction between Ti and Si3N4. The microstructure of the interface in the joint is found to be Si3N4 ceramic/TiN reaction layer/Ti5Si3 reaction layer. The grain size of the TiN and Ti5Si3 reaction layer is 0.1μm and 1-2μm, respectively. There is no crystal orientation relationship between TiN reaction layer and Si3N4 ceramic or Ti5Si3 reaction layer. The kinetic equation for calculating the thickness of the reaction layer was obtained. When a （CuZn）85Ti15 alloy is used as the filler alloy, the apparent activation energy of the growth of the reaction layer is 201.69kJ/mol.

关键词： Si3N4 ceramic Cu-Zn-Ti filler alloy interfacial reaction kinetic

Effect of Filler Composition on the Brazing of Alumina to Copper Using Ultrasonic Wave

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Journal of materials Science & Technology 2003年第Z1期19卷 176-178页

作者： Khalid m. HAFEZ masaaki naka Joining & Welding Research Institute Osaka University Ibaraki Osaka 567-0047 Japan Joining & Welding Research Institute Osaka University Ibaraki Osaka 567-0047 Japan

An ultrasonic wave was applied during brazing of alumina to Cu. First alumina was metallized by applying ultrasonicwave in braze bath. Then the metallized alumina was brazed with Cu using the same filler alloy. The filler used wereZn-Al alloys and Zn-Sn Alloys. The weight percent of Al in filler was ranging between 0, 5%, 10%, *** weight percent of tin in filler was ranging between 0, 30%, 60% and 91%, respectively. The joining mechanismwas investigated by measuring the joining strength, hardness and analyzing the microstructure at interface of thejoint. The shear strength and microstructure of the joint strongly depend on the filler composition. The effect ofultrasound was derived primarily from acoustic cavitations, impact and friction of the filler against alumina *** improved the wetting between alumina and the filler, and reflected to improve the joint strength. Anotherultrasonic advantage as to reduce of the joining temperature, that reduced the thermal stress in the braze joint.

关键词： Alumina, Copper, Ultrasonic waves, Fracture stress, microstructure, Brazing

Evaluation of the Properties of Si3N4/Si3N4 Joint Brazed Using a Filler Alloy Containing Pd

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Journal of materials Science & Technology 2003年第Z1期19卷 187-188页

作者： m. naka Jie ZHANG Yu ZHOU Joining and Welding Research Institute Osaka University Ibaraki Osaka 567-0047 Japan School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

Si3N4 ceramic was jointed to itself using a filler alloy of Cu76.5Pd8.5Ti15, and the mechanical properties of the jointwere measured and analyzed. By using a filler alloy of Cu76.5Pd8.5Ti15, the SisN4/SisN4 joints were obtained bybrazing at 1373～1473 K for 0.9～5.4 ks under a pressure of 2×10-3 mPa. The effect of brazing parameters on theshear strength of the joint was investigated. When the brazing temperature and holding time is 1423 K and 5.4 ksrespectively, the maximum shear strength of the Si3N4/Si3N4 joint is obtained to be 198 mPa.

关键词： Si3N4 ceramic, Active brazing, Ci-Pd-Ti filler alloy, Shear strength

Petrology and phase equilibrium modeling of sapphirine ＋ quartz assemblage from the Napier Complex, East Antarctica: Diagnostic evidence for Neoarchean ultrahigh-temperature metamorphism

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Geoscience Frontiers 2013年第6期4卷 655-666页

作者： Hisako Shimizu toshiaki Tsunogae m.Santosh Graduate School of Life and Environmental Sciences University of Tsukuba Department of Geology University of Johannesburg China University of Geosciences (Beijing) Division of Interdisciplinary Science Faculty of ScienceKochi University

A synthesis of the petrological characters of granulite facies rocks that contain equilibrium sapphirine ＋ quartz assemblage from two localities （Tonagh Island （TI） and Priestley Peak （PP）） in the Napier Complex,East Antarctica,provides unequivocal evidence for extreme crustal metamorphism possibly associated with the collisional orogeny during *** reaction microstructures associated with sapphirine ＋ quartz vary among the samples,probably suggesting different tectonic conditions during the metamorphic *** and quartz in TI sample were probably in equilibrium at the peak stage,but now separated by corona of Grt ＋ Sil ＋ Opx suggesting near isobaric cooling after the peak metamorphism,whereas the Spr ＋ Qtz ＋ Sil ＋ Crd ＋ Spl assemblage replaces garnet in PP sample suggesting post-peak *** application of mineral equilibrium modeling in NCKFmASHTO system demonstrated that Spr ＋ Qtz stability is lowered down to 930 ℃ due to small Fe3＋ contents in the rocks （mole Fe2O3/（FeO ＋ Fe2O3） =0.02）.The TI sample yields a peak p-T range of 950-1100 ℃ and 7.5-11 kbar,followed by cooling toward a retrograde stage of 800-950 ℃ and 8-10 kbar,possibly along a counterclockwise p-T *** contrast,the peak condition of the PP sample shows 1000-1050 ℃ and ＞12 kbar,which was followed by the formation ofSpr ＋ Qtz corona around garnet at 930-970 ℃ and 6.7-7.7 kbar,suggesting decompression possibly along a clockwise p-T *** contrasting p-T paths are consistent with a recent model on the structural framework of the Napier Complex that correlates the two areas to different crustal *** different p-T paths obtained from the two localities might reflect the difference in the tectonic framework of these rocks within a complex Neoarchean subduction/collision belt.

关键词： Ultrahigh-temperature granulite Petrology Pseudosection modeling Napier complex Antarctica

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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Kostka functions associated to complex reflection groups and a conjecture of Finkelberg-Ionov

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Science China mathematics 2018年第2期61卷 353-384页

作者： toshiaki Shoji Department of mathematics Tongji University

Kostka functions K_(λ,μ)~±(t), indexed by r-partitions λ and μ of n, are a generalization of Kostka polynomials K_(λ,μ)(t) indexed by partitions λ,μ of n. It is known that Kostka polynomials have an interpretation in terms of Lusztig's partition function. Finkelberg and Ionov(2016) defined alternate functions K_(λ,μ)(t) by using an analogue of Lusztig's partition function, and showed that K_(λ,μ)(t) ∈Z≥0[t] for generic μ by making use of a coherent realization. They conjectured that K_(λ,μ)(t) coincide with K_(λ,μ)^-(t). In this paper, we show that their conjecture holds. We also discuss the multi-variable version, namely, r-variable Kostka functions K_(λ,μ)~±(t_1,…,t_r).

关键词： Kostka functions complex reflection groups conjecture of Finkelberg-Ionov

Detrital zircon geochronology of the Lutzow-Holm Complex,East Antarctica:Implications for Antarctica-Sri Lanka correlation

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Geoscience Frontiers 2018年第2期9卷 355-375页

作者： Yusuke Takamura toshiaki Tsunogae m.Santosh Yukiyasu Tsutsumi Graduate School of Life and Environmental Sciences University of TsukubaIbaraki 305-8572Japan Department of Geology University of JohannesburgAuckland Park 2006South Africa School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China Centre for Tectonics Resources and Exploration Department of Earth SciencesUniversity of AdelaideSA 5005Australia Department of Geology and Paleontology National Museum of Nature and ScienceIbaraki 305-0005Japan

The Lützow-Holm Complex(LHC) of East Antarctica has been regarded as a collage of Neoarchean(ca.2.5 Ga), Paleoproterozoic(ca. 1.8 Ga), and Neoproterozoic(ca. 1.0 Ga) magmatic arcs which were amalgamated through the latest Neoproterozoic collisional events during the assembly of Gondwana supercontinent. Here, we report new geochronological data on detrital zircons in metasediments associated with the magmatic rocks from the LHC, and compare the age spectra with those in the adjacent terranes for evaluating the tectonic correlation of East Antarctica and Sri Lanka. Cores of detrital zircon grains with high Th/U ratio in eight metasediment samples can be subdivided into two dominant groups:(1) late meso-to Neoproterozoic(1.1-0.63 Ga) zircons from the northeastern part of the LHC in Prince Olav Coast and northern Soya Coast areas, and(2) dominantly Neoarchean to Paleoproterozoic(2.8-2.4 Ga) zircons from the southwestern part of the LHC in southern Lutzow-Holm Bay area. The ca.1.0 Ga and ca. 2.5 Ga magmatic suites in the LHC could be proximal provenances of the detrital zircons in the northeastern and southwestern LHC, respectively. Subordinate middle to late mesoproterozoic(1.3-1.2 Ga) detrital zircons obtained from Akarui Point and Langhovde could have been derived from adjacent Gondwana fragments(e.g., Rayner Complex, Eastern Ghats Belt). meso-to Neoproterozoic domains such as Vijayan and Wanni Complexes of Sri Lanka, the southern madurai Block of southern India, and the central-western madagascar could be alternative distal sources of the late meso-to Neoproterozoic zircons. Paleo-to mesoarchean domains in India, Africa, and Antarctica might also be distal sources for the minor ~2.8 Ga detrital zircons from Skallevikshalsen. The detrital zircons from the Highland Complex of Sri Lanka show similar Neoarchean to Paleoproterozoic(ca. 2.5 Ga) and Neoproterozoic(ca. 1.0 Ga) ages, which are comparable with those of the LHC, suggesting that the two complexes might have form

关键词： The northern Lützow-Holm-Vijayan Complex Zircon U-Pb geochronology Crustal evolution Tectonic correlations Gondwana supercontinent

Performance and Internal Flow of a Counter-rotating Type Tidal Stream Turbine

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Journal of Thermal Science 2015年第5期24卷 410-416页

作者： Bin Huang toshiaki Kanemoto Faculty of Engineering Kyushu Institute of Technology

In the past decade, the tidal energies have caused worldwide concern as it can provide regular and predictable re- newable energy resource for power generation. The majority of technologies for exploiting the tidal stream energy are based on the concept of the horizontal axis propellers, which can be derived from the design and operation of wind turbines. However, there are some peculiar features such as the propeller working in the seawater with free surface and the possible occurrence of cavitation as compared with wind turbines. Especially, for a coun- ter-rotating type tidal stream power turbine, it is difficult to accurately predict the interaction between the front and rear blades at the design stage by blade element momentum theory. As a result, CFD shows its advantage to predict the performance of counter-rotating type propellers of the tidal stream turbi^le. In order to improve the accuracy of CFD predictions, the predicted results must be verified with experimental values. In this paper, a CFD model using block-structured grid was set up and experimental test was performed in a water tunnel for a tidal stream turbine with counter-rotating type propellers. The comparison between CFD predictions and experimental data shows quite good agreement on the power coefficients, which provides an evidence of validation of the CFD model. Such results offer the necessary confidence in the accuracy of the set up CFD model for the coun- ter-rotating type tidal stream turbine.

关键词： Counter-rotating tidal stream turbine internal flow CFD experimental validation

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