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Volatiles in the mantle transition zone and their effects on big mantle wedge systems

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National Science Review 2024年第6期11卷 15-18页

作者： Yu Wang yi-gang Xu State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)

The mantle transition zone (MTZ), located between the upper and lower mantle, is characterized by sudden seismicvelocity discontinuities at depths of 410 and 660 km where significant change in mineralogical composition occurs. As a link between the upper and lower mantle,the MTZ is a layer of special significance in Earth’s deep structure, and a critical interface in geodynamics and material circulation.

关键词： systems effects mantle their transition volatiles wedge zone

Higher pressure differentiation of arc magmas under thicker crust

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National Science Review 2023年第3期10卷 100-101页

作者： yi-gang Xu State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)

The formation of continental crust is pivotal to understanding the evolution of the earth and its *** average intermediate or’andesitic’bulk composition and characteristic depletion of niobium of the continental crust are strikingly matched by convergent margin magmas [1].This has led to the inference that most continental crust is derived from igneous,arc ***,continental crust has characteristically higher Mg#(>0.5) than most oceanic arc andesites (<0.5).

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NUMERICAL SIMULATION OF FISH SWIMMING WITH RIGID PECTORAL FINS

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Journal of Hydrodynamics 2012年第2期24卷 263-272页

作者： XU yi-gang WAN De-cheng State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The numerical simulation of the self-propelled motion of a fish with a pair of rigid pectoral fins is presented.A Navier-Stokes equation solver incorporating with the multi-block and overset grid method is developed to deal with the multi-body and moving body *** lift-based swimming mode is selected for the fin *** the lift-based swimming mode,the fin can generate great thrust and at the same time have no generation of lift *** can be found when a pair of rigid pectoral fins generates the hydrodynamic moment,it may also generate a lateral force opposite to the centripetal direction,which has adverse effect on the turn motion of the ***,the periodic vortex structure generation and shedding,and their effects on the generation of hydrodynamic force are also demonstrated in this article.

关键词： pectoral fins lift-based swimming mode self-propelled motion overset grid method

Microstructure and mechanical property of Sn–Ag–Cu solder material

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Rare Metals 2017年第3期36卷 193-197页

作者： yi-gang Kong Zhi-gang Kong Feng-Min Shi School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Research Laboratory of Electrical Contacts Beijing University of Posts and TelecommunicationsBeijing 100876China Technology Department Jinan No.10 Radio Factory Co.Ltd.Jinan 250100China

Among the lead-free solder materials,Sn-Ag-Cu alloys have many advantages,such as good wetting property,superior interfacial properties and high creep *** this article,the organization and welding performance of Sn-Ag-Cu material were *** surface morphology of the two alloys was observed by stereoscopic microscope and scanning electron microscope （SEM）.Chemical constitution was examined by X-ray energy-dispersive spectroscopy （EDS）.The mechanical properties of Sn-Ag-Cu solder were evaluated systematically compared with those of Sn-Cu *** results show that Sn-Ag-Cu solder based on different solder pads has different welding *** thickness of intermetallic compound （IMC） at the interface increases with aging *** the gold-plated pads,there are a large number of IMC graphic,and in the welding interface,it can reduce the reliability of electrical *** Sn-Ag-Cu solder joints show a superior mechanical property over the traditional Sn-Cu *** number of dimples decreases and that of cavities increases for Sn-Cu0.7 alloy and the fracture surfaces of Sn-Ag3.0-Cu0.5 alloy have many small size dimples which are homogeneously distributed.

关键词： Lead-free solder Organization Weldingperformance Intermetallic compound

Radiative Decay Bc → Ds*γ in the Technicolor with a Massless Scalar Doublet Model

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Communications in Theoretical Physics 2002年第7期38卷 47-52页

作者： CAO yi-gang JIAO Zheng-Kuan Department of Physics Zhejiang University Hangzhou 310027 China Department of Physics Zhejiang University Hangzhou 310027 China

Applying perturbative QCD, we study the process Bc → Dsγ in the technicolor with a massless scalar doublet model (TCMLSM). There are mainly two mechanisms contributing to the Bc → D*sγ process. One proceeds through the short distance b → sγ transition and the other through weak annihilation accompanied by a photon *** find that, compared with the standard model, the modification of Bc → D*sγ from πρ (the physical pions in the TCMLSM) is so small that can be neglected for the allowed mass ofπρ. The weak-annihilation contribution is found to be about one order larger than that of the electromagnetic penguin diagrams.

关键词： perturbative QCD, technicolor, massless scalar doublet model

Synthesize of Metallic Glasses in Immiscible Mo-Cu System by Ion Mixing of Multilayers

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Chinese Physics Letters 1997年第3期14卷 194-197页

作者： CHEN yi-gang LIU Bai-xin Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084 State Key Laboratory of Solid-state Microstructures Physics Nanjing UniversityNanjing 210093

In the properly designed Mo-Cu multilayered films by free energy concern,several new metallic glasses,were obtained by ion mixing in an immiscible Mo-Cu *** elucidate the unexpected glass formation,a Gibbs free energy diagram was constructed on the basis of Miedema’s model,with a special consideration to include the interfacial free energy into the initial state of the multilayered *** turned out that the interfacial free energy raised the multilayered films to an energetic state higher than that of the amorphous phase in a specific range depending on the fraction of interfacial atoms and that the ion-induced glass transition observed in this system was generated by the interfaces.

关键词： interfacial glass glasses

Anomalous Scaling of Surface Growth Equations with Spatially and Temporally Correlated Noise

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Communications in Theoretical Physics 2008年第7期50卷 227-230页

作者： XIA Hui TANG gang LI yi-Fan Department of Physics China University of Mining and Technology Xuzhou 221008 China

Based on the scaling idea of local slopes by Lopez et al. [Phys. Rev. Lett. 94 （2005） 166103], we investigate anomalous dynamic scaling of （d ＋ 1）-dimensional surface growth equations with spatially and temporally correlated noise. The growth equations studied include the Kardar-Parisi-Zhang （KPZ）, Sun-Guo-Grant （SGG）, and Lai-Das Sarma-Villain （LDV） equations. The anomalous scaling exponents in both the weak- and strong-coupling regions are obtained, respectively.

关键词： surface growth equation local slope fluctuations anomalous dynamic scaling

Depinning Dynamics of Two-Dimensional Charged Colloids on a Random Laser-Optical Substrate

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Communications in Theoretical Physics 2009年第5期51卷 938-940页

作者： CAO yi-gang WANG Hong-Ling YANG gang HAN Hong-Pei School of Physics and Engineering Zhengzhou University Zhengzhou 450001 China Information College of Electronic-Engineering Xuchang University Xuchang 310018 China

Using Langevin simulations, we. investigate the depinning dynamics of two-dimensional charged colloids on a random laser-optical substrate. With an increase in the strength of the substrate, we find a transition from crystal to smectic flows above the depinning. A power-law scaling relationship between average velocity and applied driving force could be obtained for both flows, and we find that the scaling exponents are no bigger than 1 for the crystal and are bigger than 1 for the smectic flows.

关键词： charged colloids laser-optical substrate depinning

NUMERICAL SIMULATION OF TOPOGRAPHY CHANGE IN RECLAIMED LAND ALONG COAST OF SOUTH CHINA SEA

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Journal of Hydrodynamics 2002年第1期14卷 87-92页

作者： Li, Xi Wang, yi-gang Sha, Shu-Ming Res. Inst. of Coastal and Ocean Eng. Hohai Univ. Nanjing 210029 China

A formula for total sediment transport rate was worked out based on field surveys and experiments, which could be used to predict the topography change under wave climate. The sediment transport and wave induced hydrodynamics were solved separately, which is more convenient to predict long-term beach evolution than solving a coupled equation. In applying the sediment transport equation to wave model, the topography change was considered to give a new bathymetry as input for the wave equations, which in return will give a time-dependent hydrodynamic environment. The wave transformation including wave breaking was simulated by solving Boussinesq-type wave equations, together with some verification and comparisons. The longshore currents due to eddy viscosity was simulated by the model under unidirectional waves, which have been applied in erosion control of reclaimed land by headland breakwaters. The topography is found in equilibrium by headland breakwaters and the equilibrium process is simulated with comparison to the engineering practice in the South China Sea.

关键词： Coastal zones Computer simulation Erosion Mathematical models Viscosity