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Elliptical Galaxies with Emission Lines from the Sloan Digital Sky Survey

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 15-24页

作者： Ying-He Zhao Qiu-sheng Gu zhi-xin Peng Lei Shi xin-Lian Luo Qiu-He Peng Department of Astronomy Nanjing University Nanjing 210093

As part of a study of star formation history along the Hubble sequence, we present here the results for 11 elliptical galaxies with strong nebular emission lines. After removing the dilution from the underlying old stellar populations by use of stellar population synthesis model, we derive the accurate fluxes of all the emission lines in these objects, which are then classified, using emission line ratios, into one Seyfert 2, six LINERs and four HII galaxies. We also identify one HII galaxy （A1216＋04） as a hitherto unknown Wolf-Rayet galaxy from the presence of the WolfRayet broad bump at 4650A. We propose that the star-forming activities in elliptical galaxies are triggered by either galaxy-galaxy interaction or the merging of a small satellite/a massive star cluster, as has been suggested by recent numerical simulations.

关键词： Galaxies: elliptical and lenticular cD Galaxies: starburst - Galaxies:individual: A1212+06 A1216+04 CGCG13-83 IC 225

All-Optical Time Slot Interchange Using a Cascaded Optical Buffer

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Chinese Physics Letters 2012年第8期29卷 93-95页

作者： FENG Zhen sheng xin-zhi WU Chong-Qing LI Zheng-Yong MAO Ya-Ya Key Lab of Luminescence and Optical Information Technology(Ministry of Education) Beijing Jiaotong UniversityBeijing 100044

A novel scheme of all-optical time slot interchanger employing two cascaded re-circulating optical buffers based on nonlinear polarization rotation in semiconductor optical amplifiers is *** experimental system exhibits full interchangeable capability on three 512-bit packets at 10 Gbits/***,each packet length is up to 123 ns with the maximum buffer depth 30%.

关键词： polarization optical Slot

Microphase Separation of Semiflexible Ring Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第2期42卷 267-276,I0011页

作者： Dan-Yan Qin sheng-Da Zhao zhi-xin Liu Jing Zhang xing-Hua Zhang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the difficult problem of solving the conformation statistics of complex polymers, this study presents a novel and concise conformation statistics theoretical approach based on Monte Carlo and Neural Network method. This method offers a new research idea for investigating the conformation statistics of complex polymers, characterized by its simplicity and practicality. It can be applied to more complex topological structure, more higher degree of freedom polymer systems with higher dimensions, theory research on dynamic self-consistent field theory and polymer field theory, as well as the analysis of scattering experimental data. The conformation statistics of complex polymers determine the structure and response properties of the system. Using the new method proposed in this study, taking the semiflexible ring diblock copolymer as an example, Monte Carlo simulation is used to sample this ring conformation to construct the dataset of polymer. The structure factor describing conformation statistics are expressed as continuous functions of structure parameters by neural network supervised learning. This is the innovation of this work. As an application, the structure factors represented by neural networks were introduced into the random phase approximation theory to study the microphase separation of semiflexible ring diblock copolymers. The influence of the ring's topological properties on the phase transition behavior was pointed out.

关键词： Ring copolymer Diblock copolymers Semiflexible The order-disorder transition

Electrical characteristics of a fractional-order 3×n Fan network

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Communications in Theoretical Physics 2024年第4期76卷 176-187页

作者： zhi-Zhong Tan xin Wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is *** the first step,the RT-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan *** the second part,the effects of five system parameters(L,C,n,α and β)on amplitude-frequency and phase-frequency characteristics are *** the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab *** work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics RT-V theory

Nonlinear metamaterial enabled aeroelastic vibration reduction of a supersonic cantilever wing plate

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1749-1772页

作者： Peng sheng xin FANG Dianlong YU Jihong WEN Laboratory of Science and Technology on Integrated Logistics Support College of Intelligence Science and TechnologyNational University of Defense TechnologyChangsha 410073China

The violent vibration of supersonic wings threatens aircraft *** paper proposes the strongly nonlinear acoustic metamaterial(NAM)method to mitigate aeroelastic vibration in supersonic wing *** employ the cantilever plate to simulate the practical behavior of a *** aeroelastic vibration model of the NAM cantilever plate is established based on the mode superposition method and a modified third-order piston *** aerodynamic properties are systematically studied using both the timedomain integration and frequency-domain harmonic balance *** presenting the flutter and post-flutter behaviors of the NAM wing,we emphasize more on the preflutter broadband vibration that is prevalent in *** results show that the NAM method can reduce the low-frequency and broadband pre-flutter steady vibration by 50%-90%,while the post-flutter vibration is reduced by over 95%,and the critical flutter velocity is also slightly *** clarified,the significant reduction arises from the bandgap,chaotic band,and nonlinear resonances of the NAM *** reduction effect is robust across a broad range of parameters,with optimal performance achieved with only 10%attached *** work offers a novel approach for reducing aeroelastic vibration in aircraft,and it expands the study of nonlinear acoustic/elastic metamaterials.

关键词： nonlinear acoustic metamaterial(NAM) hypersonic aeroelastic vibration vibration reduction fluid-structure interaction

I_(2)-DMSO-Mediated Multicomponent [2+1+1+1] Annulation Reaction via Ethyl Nitroacetate C-NO_(2), Bond Cleavage as a C1 Synthon: A Route to Multisubstituted 6-Pyrrolidinones Derivatives with a Quaternary Center

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Chinese Journal of Chemistry 2024年第17期42卷 2029-2034页

作者： zhi-Cheng Yu Xi Shen You Zhou Xiang-Long Chen Li-sheng Wang Yan-Dong Wu An-xin Wu National Key Laboratory of Green Pesticide International Joint Research Centerfor Intelligent BiosensorTechnologyand HealthCollegeof ChemistryCentral ChinaNormal UniversityWuhanHubei 430079China

A[2+1+1+1]cyclization reaction has been developed for the synthesis of multisubstituted 6-pyrrolidinones from commercially available aryl methyl ketones,primary amines,and ethyl *** this I_(2)-DMSO-meditated process,the C-NO_(2) bond of ethyl nitroacetate is cleaved,affording a C1 synthon,and the formation of two C-C and two C-N bonds and a quaternary carbon center are constructed in one *** method has good substrate compatibility and permits the late-stage modification of pharmaceutical compounds.

关键词： Cyclization Multisubstituted 6-pyrrolidinones I_(2)-DMSO C1 building blocks Quaternary carbon center Late-stage modification Cracking

Wettability and corrosion behavior between alkaline slag from sodium smelting of vanadium-titanium magnetite and refractory substrates

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Journal of Iron and Steel Research International 2024年第6期31卷 1399-1410页

作者： Fei Zhao zhi-wei Bian Hong-xin Zhao De-sheng Chen Zhang-fu Yuan Yu-lan Zhen Li-na Wang Tao Qi Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China National Engineering Research Center of Green Recycling for Strategic Metal Resources Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Hebei Zhongke Tongchuang Vanadium&Titanium Technology Co. Ltd.Hengshui 053000HeheiChina

The sodium smelting of vanadium-titanium magnetite can achieve the comprehensive utilization of Fe,V,and ***,the generation of alkaline slag during this process may cause damage to refractory *** wettability and corrosion behavior of alkaline slag on three types of refractory(MgO-C,SiC,and high alumina refractory)substrates were investigated at temperatures up to 1200℃.The effects of duration on the wettability of molten slag on SiC substrates were also *** showed that the high alumina refractory exhibited better wettability with the molten slag than the others,and thus,it is easier to be *** results of scanning electron microscopy coupled with energy dispersive spectroscopy showed that MgO-C and high alumina refractory substrates were severely *** was a visible and regular interfacial reaction layer between the slag and SiC refractory substrate,which was produced by the redox reaction between the metal oxides in the slag and the SiC refractory *** the increase in holding time,the interface layer expands and silico-ferrite phases are generated at the *** redox reaction between Fe_(2)O_(3) and SiC substrate is the main reason for the *** comparing the differences in wettability and corrosion behavior between the alkaline slag from sodium smelting of vanadium-titanium magnetite and MgO-C,SiC and high alumina refractories,it is concluded that SiC refractory has good corrosion resistance to the *** oxides in the slag accelerate the oxidation rate of SiC refractory.

关键词： Wettability Corrosion Alkaline slag-Contact angle Vanadium-titanium magnetite Refractory

The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

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Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu Mao sheng Xiao-Ying Zhuang xin-Yi Li Gen-sheng Li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： Zhong-lin Wang zhi-hua Gong Quan Li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation