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China Geology 2025年第1期8卷 230-232页

作者： Yuan-yuan Feng Ya-dong Li An-kai Geng liu-an duan Da-dou Li No.1 Geological Team of Shandong Province Bureau of Geology and Mineral Resources Jinan 250100China Yantai Geological Survey Center of Coastal Zone China Geological SurveyYantai 264004China

*** Three stages of Mesozoic magmatic activity have been identified in the Jiaodong area,namely early magmatic emplacement,the magmatic emplacement prior to mineralization,and magmatic activity post-mineralization,fro... 详细信息

关键词： dating belt mineralization

Investigation of Anti-Plane Shear Behavior of a Piezoelectric Material Containing an Impermeable Edge Crack

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上海交通大学学报 2004年第Z2期38卷 124-129页

作者： Shijie duan Shuhong liu Jin liu School of Adult Education Shijiazhuang Railway InstituteShijiazhuang 050043 China Department of Mechanics and Engineering Science Shijiazhuang Railway InstituteShijiazhuang 050043 China Department of Mechanics and Engineering Science Shijiazhuang Railway InstituteShijiazhuang 050043 China

The problem involving an edge-crack in a rectangular material under the anti-plane mechanical loading and in-plane electric loading is analyzed under the impermeable conditions. By using the series expansion, the general solutions of electromechanical fields are obtained, which satisfied both governing equations and crack sufrace boundary conditions, and the unknown constants in which can be obtained by the boundary collocation method. Numerical results are given to show the effect of electromechanical interaction on energy release rate.

关键词： piezoelectric material mode-Ⅲ edge-crack intensity factor energy release rate boundary collocation method

X-ray afterglow of GRB 050712: multiple energy injections into the external shock

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Research in Astronomy and Astrophysics 2014年第5期14卷 610-616页

作者： Liang-duan liu A-Ming Chen Institute of Astrophysics Central China Normal University School of Astronomy and Space Science Nanjing University

As indicated by observed X-ray flares, a great amount of energy can be in- termittently released from the postburst central engine of gamma-ray bursts （GRBs）. As a natural consequence, the GRB＇s external shock could be repeatedly energized. With such a multiple energy injection model, we explore the unique X-ray afterglow light curve of GRB 050712, which exhibits four shallow decay plateaus. Together with three early X-ray flares, the celatral engine of GRB 050712 is believed to have released energy at least seven times after the burst. Furthermore, we find that the ener- gies released during the four plateaus are all on the same order of magnitude, but the luminosity significantly decreased with time. These results may provide some inter- esting implications for the GRB central engine.

关键词： gamma rays: bursts -- individual: GRB 050712

LATTICE BOLTZMANN SIMULATIONS OF TRIAGULAR CAVITY FLOW AND FREE-SURFACE PROBLEMS

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Journal of Hydrodynamics 2007年第2期19卷 127-134页

作者： duan Ya-li liu Ru-xun Department of Mathematics University of Science and Technology of China Hefei 230026 China

The Lattice Boltzmann Method （LBM） was investigated to solve triangular cavity flow and free-surface problems in hydraulic dynamics. Some cases of triangular cavity flow and backward step flow were simulated to show the efficiency and stability of this method. Two-dimensional partial dam breaking problem and the propagation and diffraction of dam-break wave around rectangular and circular cylinder were numerically studied successfully. Excellent agreement was obtained between numerical predictions and available results.

关键词： Lattice Boltzmann Method (LBM) triangularcavity flow shallow water equations dam breaking

Geological and Geochemical Constraints on the Newly Discovered Yangchongli Gold Deposit in Tongling Region, Lower Yangtze Metallogenic Belt

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2078-2108页

作者： duan liu'an GU Huangling YANG Xiaoyong CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of China Institute of Geology and Geophysics Chinese Academy of Sciences No.7 Gold Geological Party of CAPF School of City and Environment Hunan University of Technology

The newly discovered Yangchongli gold deposit is a unique independent gold deposit in the Tongling ore-cluster region controlled by the tectonic alteration firstly discovered in the Lower Yangtze Metallogenic Belt （LYMB）. The host magmatic rocks mainly consist of monzodiorite and K-feldspar granite. The LA-ICP-MS U-Pb zircons dating yielded weighted mean 206pb/23SU ages of 140.7 ± 1.8 Ma and 126.4 ±1.2 Ma for the monzodiorite and K-feldspar granite, respectively. Monzodiorites are enriched in Sr, Ba, Rb, and depleted in Y, Yb with high Sr/Y and La/Yb ratios, similar to the geochemical features of adakite, considered as products of differentiation of mafic magmas originating from lithospheric mantle melt/fluids caused by metasomatism during paleo-Pacific Plate subduction in the Mesozic. In contrast, the compositions of K-feldspar granites are A-type granites, indicating an extensional tectonic background. Gold ores hosted in the fracture zone occurred as quartz vein within cataclastic rock. Sulfur and lead isotopes from pyrites show crust-mantle mixing characteristics. Metal components from strata also took part in the gold mineralization, and resulted from two episodes of magmatism that were probably related to tectonic transition from a compressive to an extensional setting between 140-126 Ma, which led to the Mesozoic large-scale polymetallic mineralization events in eastern China.

关键词： monzodiorites A-type granites U-Pb chronology Yangchongli gold deposits Tongling region Lower Yangtze Metallogenic Belt

Spin flip in single quantum ring with Rashba spin–orbit interation

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Chinese Physics B 2018年第3期27卷 397-400页

作者： duan-Yang liu Jian-Bai Xia College of Science Beijing University of Chemical Technology Beijing 100029 China State Key Laboratory for Superlattice and Microstructures Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

We theoretically investigate spin transport in the elliptical ring and the circular ring with Rashba spin-orbit interaction. It is shown that when Rashba spin-orbit interaction is relatively weak, a single circular ring can not realize spin flip, however an elliptical ring may work as a spin-inverter at this time, and the influence of the defect of the geometry is not obvious. Howerver if a giant Rashba spin-orbit interaction strength has been obtained, a circular ring can work as a spin-inverter with a high stability.

关键词： Rashba spin-orbit interaction quantum waveguide Aharonov-Bohm ring spin flip spin device

THE FINITE VOLUME PROJECTION METHOD WITH HYBRID UNSTRUCTURED TRIANGULAR COLLOCATED GRIDS FOR INCOMPRESSIBLE FLOWS

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Journal of Hydrodynamics 2009年第2期21卷 201-211页

作者： GAO Wei duan Ya-li liu Ru-xun Department of Mathematics University of Science and Technology of China Hefei 230026 China

In this article a finite volume method is proposed to solve viscous incompressible Navier-Stokes equations in two-dimensional regions with corners and curved boundaries. A hybrid collocated-grid variable arrangement is adopted, in which the velocity and pressure are stored at the centroid and the circumcenters of the triangular control cell, respectively. The cell flux is defined at the mid-point of the cell face. Second-order implicit time integration schemes are used for convection and diffusion terms. The second-order upwind scheme is used for convection fluxes. The present method is validated by results of several viscous flows.

关键词： incompressible viscous flows Navier-Stokes equations finite volume method projection method unstructured collocated grid

Dinuclear gold-catalyzed C–H bond functionalization of cyclopropenes

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Science China Chemistry 2021年第11期64卷 1958-1963页

作者： Kai liu Tingrui Li duan-Yang liu Weipeng Li Jian Han Chengjian Zhu Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China College of Chemical Engineering Zhejiang University of TechnologyHangzhou310014China College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou450001China Advanced Catalytic Engineering Research Center of the Ministry of Education Hunan UniversityChangsha410082China

We report an unprecedented C-H bond functionalization of cyclopropenes enabled by dinuclear gold *** selective C-H allylation,alkynylation and halogenation of cyclopropenes with organic halides have been *** reaction does not require strong external oxidants and affords access to functionalized cyclopropenes in moderate to good *** reductive elimination process to controllably construct C-C or C-X bonds can be tuned by using different dinuclear gold catalysts.

关键词： cyclopropenes gold catalysis allylation alkynylation C–H activation

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Oscillating chemiluminescence in rhodamine B-induced Belousov-Zhabotinsky reaction catalyzed by Ce(Ⅳ)

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Chinese Science Bulletin 2009年第11期54卷 1901-1907页

作者： duan ChunFeng liu GuangMing ZHANG ZhiFeng CUI Hua Department of Chemistry University of Science and Technology of China Hefei 230026 China

It was found that rhodamine B could induce oscillating chemiluminescence (OCL) from the Ce4+-cata-lyzed Belousov-Zhabotinsky reaction. This new OCL system, i.e., rhodamine B-malonic acid-bromate-Ce(Ⅳ)-sulfuric acid, exhibited two clearly distinguished emission peaks in each oscillation period. The initial concentrations of the reactants strongly influenced the oscillation pattern. For the study of the CL mechanism, a platform for a versatile and simultaneous potential and CL measurement was estab-lished to compare the potential oscillation with the CL oscillation behavior of this system. The CL spectra, UV-visible absorption spectra and time-resolved fluorescence spectra of this OCL system were studied. A possible, simplified mechanism for the OCL is proposed. It is suggested that the generation of the two CL peaks is likely due to the oxidation of the intermediate of rhodamine B by Ce(Ⅳ) and Br2, respectively. This work provided a new method and platform to research the complex chemical oscilla-tions.

关键词：罗丹明B 振荡周期化学发光反应诱导催化时间分辨荧光光谱紫外可见吸收光谱

Mineralization,Geochemistry and Zircon U-Pb Ages of the Paodaoling Porphyry Gold Deposit in the Guichi Region,Lower Yangtze Metallogenic Belt,Eastern China

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 706-732页

作者： duan liu'an YANG Xiaoyong DENG Jianghong WANG Fangyue LEE Insung CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of China Hefei 230026 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China No. 7 Gold Geological Party of the Chinese People's Armed Police Force Yantai 264004 Shandong China Laboratory for Marine Mineral Resourees Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 Shandong China Center of Deep Sea Research Institute of Oceanography Chinese Academy of Sciences Qingdao 266071 Shandong China School of Resources and Environmental Engineering Hefei University of Technology Hefei 230009 China School of Earth and Environmental Sciences Seoul National University Seoul 151- 742 Korea

The newly discovered Paodaoling porphyry Au deposit from the Guichi region, Lower Yangtze River Metallogenic Belt （LYRB）, contains 〉35 tons of Au at an average grade of -1.7 g/t. It is a porphyry ＇Au-only＇ deposit, as revealed by current exploration in the depths, mostly above -400 m, which is quite uncommon among coeval porphyry mineralization along the LYRB. Additionally, there are also Cu-Au bearing porphyries and barren alkaline granitoids in the Paodaoling district. Zircon LA-ICP-MS U-Pb dating of the Cu-Au-bearing porphyries yield an age of 141-140 Ma, falling within the main magmatic stage of the LYRB, whereas the barren granites give an age of 125-120 Ma, coeval with the regional A- type granites. The Cu-Au-bearing porphyries are LILE-, LREE-enriched and HFSE-depleted, typical of arc magmatic affinities. The barren granites are HFSE-enriched, with lower LREE/HREE ratios and pronounced negative Eu anomalies. The Cu-Au-bearing porphyries in the Paodaoling district have high oxygen fugacities and high water content. Pyrite sulfur isotopes of the Paodaoling gold deposit indicate a magmatic-sedimentary mixed source for the ore-forming fluids. Based on the alteration and poly-metal zonation of the deepest exploration drill hole from the Paodaoling Au deposit, we propose that Cu ore bodies could lie at depth beneath the current Au ore bodies. The magmatism and associated Cu-Au mineralization of the Paodaoling district are likely to have formed in a subduction setting, during slab rollback of the paleo-Pacific plate.

关键词： zircon U-Pb dating porphyry Au deposit Lower Yangtze River metallogenic belt (LYRB),Paodaoling paleo-Pacific plate subduction