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The maximal Lyapunov exponent of a co-dimension two-bifurcation system excited by a bounded noise

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Acta Mechanica Sinica 2012年第2期28卷 511-519页

作者： Sheng-Hong Li Xian-bin liu State Key Lab of Mechanics and Control for Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics210014 NanjingChina School of Mathematics and Physics Jiangsu University of Science and Technology212003 ZhenjiangChina

In the present paper, the maximal Lyapunov ex- ponent is investigated for a co-dimension two bifurcation system that is on a three-dimensional central manifold and subjected to parametric excitation by a bounded noise. By using a perturbation method, the expressions of the invari- ant measure of a one-dimensional phase diffusion process are obtained for three cases, in which different forms of the matrix B, that is included in the noise excitation term, are assumed and then, as a result, all the three kinds of singular boundaries for one-dimensional phase diffusion process are analyzed. Via Monte-Carlo simulation, we find that the an- alytical expressions of the invariant measures meet well the numerical ones. And furthermore, the P-bifurcation behav- iors are investigated for the one-dimensional phase diffusion process. Finally, for the three cases of singular botmdaries for one-dimensional phase diffusion process, analytical ex- pressions of the maximal Lyapunov exponent are presented for the stochastic bifurcation system.

关键词： Maximal Lyapunov exponent Perturbationmethod. Bounded noise. Diffusion process

Synergetic effect between sulfurized Mo/γ-Al_2O_3 and Ni/γ-Al_2O_3 catalysts in hydrodenitrogenation of quinoline

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Journal of Natural Gas Chemistry 2011年第2期20卷 214-217页

作者： Lihua liu bin liu Yongming Chai Yunqi liu Chenguang liu State Key Laboratory of Heavy Oil Processing Key Laboratory of Catalysis CNPC China University of Petroleum （East China） Qingdao 266555 Shandong China

An evidence for the synergetic effect between the stacked bed of Mo/γ-Al2O3 and Ni/γ-Al2O3 in the hydrodenitrogenation （HDN） reaction of quinoline has been provided in this paper. The synergism factor decreases when the reaction temperature increases （280？340 ？C）. The synergetic effect leads to improve the hydrogenation activity for the stacked bed compared with the single Mo/γ-Al2O3 bed, which may be attributed to the generation of hydrogen spillover on the Ni/γ-Al2O3 catalyst.

关键词： hydrogen spillover synergetic effect hydrodenitrogenation NiMo catalyst

Synthesis of 1,2-phenylenedimethanols by base-promoted reduction of isobenzofuran-1(3H)-ones with silane

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Chinese Chemical Letters 2019年第3期30卷 725-728页

作者： bin liu Xigeng Zhou Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan University Technology Research Insititute of Shanghai Huayi (Group) Company

An efficient method for preparation of substituted 1,2-phenylenedimethanols and aliphatic 1,4-diols that are valuable intermediates in organic synthesis, has been developed by the base-promoted reduction of isobenzofuran-1(3H)-ones and y-lactones with silane under mild conditions. Compared with traditional procedures using stoichiometric amounts of metal hydrides and alkyl reductants, the present method avoids the use of sensitive reagents and is operationally simple and a broad variety of functional groups are tolerated.

关键词： Isobenzofuran-1(3H)-one 1,2-Phenylenedimethanol Reductive transformation Ring-opening reaction Silane

Structure function analysis of RISS and model-fitting to J1128+5925

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Research in Astronomy and Astrophysics 2015年第1期15卷 37-44页

作者： bin liu Bo Peng Li-Jia liu National Astronomical Observatories Chinese Academy of Sciences

There has been great progress recently in the study of radio variability, including the phenomenon of intraday variability（IDV） which occurs on short timescales of 50 h or less. There are two common explanations for IDV： an intrinsic mechanism or the effect of radio propagation through the interstellar medium. We consider the case of refractive interstellar scintillation（RISS）, an extrinsic cause of radio variability. We theoretically derive the structure function of the ‘thick screen’RISS model by using an approximation method, and discuss its application to the IDV phenomenon with some simulated results. Finally, the IDV source J1128＋5925 is fitted with the ‘thin screen’ RISS model. Some possible combinations of parameters, namely source size, distance and relative velocity of the scattering screen, are presented.

关键词： radio variable source refractive scintillation structure function,IDV

Effect of Al_(2)O_(3)fiber on twin intersections-induced dynamic recrystallization in fine-grained TiAl matrix composite

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Journal of Materials Science & Technology 2024年第5期172卷 1-14页

作者： Yaofeng Luo Yan Wang Li Wang bin liu Yong liu State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl ***,the underlying DRX mechanism remains poorly *** this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction *** addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first *** re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic *** origin of the twin intersection and TDRX for the composite was *** stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin *** high stored strain energy at the regions of twins and twin intersections provided the driving force for *** accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)*** present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites.

关键词： TiAl matrix composite Al_(2)O_(3)fiber Twin intersection Dynamic recrystallization

Existence of Periodic Solutions for p-Laplacian Equation under the Frame of Fuoik Spectrum

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Acta Mathematica Sinica,English Series 2011年第3期27卷 545-554页

作者： Wen bin liu Yong LI Department of Mathematics China University of Mining and Technology Xuzhou 221008 P. R. China College of Mathematics Jilin University Changchun 130012 P. R. China

In this paper, under the frame of Fuoik spectrum, we study the existence of periodic solutions for p-Laplacian equation by asymptotic behaviors of potential function, improve some results to some extent.

关键词： p-Laplacian equation periodic solution Fuoik spectrum potential function

Existence Results for Impulsive Neutral Stochastic Evolution Inclusions in Hilbert Space

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Acta Mathematica Sinica,English Series 2011年第7期27卷 1405-1418页

作者： Han Wen NING bin liu School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan 430074 P. R. China

This paper is concerned with the existence of mild solutions of a class of impulsive neutral stochastic evolution inclusions in Hilbert space in the case where the right hand side is convex or nonconvex-valued. The re... 详细信息

关键词： Impulsive mild solutions stochastic evolution inclusions convex nonconvex

Nanocomposites of CsPbBr_(3) perovskite quantum dots embedded in Gd_(2)O_(3):Eu^(3+) hollow spheres for LEDs application

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Journal of Rare Earths 2022年第10期40卷 1509-1518页

作者： Gang Wang Shangjun Yu bin liu Zongming liu Jinkai Li School of Materials Science and Engineering University of JinanJjinan 250022China

Gd_(2)O_(3):Eu^(3+)@CsPbBr_(3) quantum dots(QDs)mesoporous hollow nanocomposites with good luminescent properties and high stability were *** which,the hollow Gd_(2)O_(3):Eu^(3+)spheres and CsPbBr_(3) QDs were prepared by urea homogeneous precipitation and hot-injection method,***,the Gd_(2)O_(3):Eu^(3+)@CsPbBr_(3) QDs shell-core compounds were constructed through mechanical *** structure,morphology,stability and luminescent properties were studied by Fourier transform infrared spectroscopy(FT-IR),differential scanning calorimetry/thermogravity(DSC/TG),X-ray diffraction(XRD),field-emission scanning electron microscopy(FE-SEM),transmission electron microscopy(TEM),photoluminescence excitation/photoluminescence(PLE/PL)and life decay *** to the original CsPbBr_(3) QDs,Gd_(2)O_(3):Eu^(3+)@CsPbBr_(3) QDs display better photostability,thermal stability and current *** resulting Gd_(2)O_(3):Eu^(3+)@CsPbBr_(3) QDs composite exhibits good yellow *** Gd_(2)O_(3):Eu^(3+)@CsPbBr_(3) QDs mixed silicone resin was directly coated on the blue LED chip,then the w-LED device with the color coordinate of(0.31,0.32)was successfully *** Gd_(2) O_(3):Eu^(3+)@CsPbBr_(3) QDs compounds with excellent luminescent properties and stability are expected to be widely used in lighting and display areas.

关键词： Rare earth oxides Hollow mesoporous Stability Perovskite quantum dot Light-emitting diode

Red color Sr_(2)NaMg_(2)V_(3)O_(12):Eu^(3+)phosphor with high thermal stability for w-LEDs

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Journal of Rare Earths 2023年第11期41卷 1689-1695,I0002页

作者： Jinkai Li bin liu Guiyuan liu Quande Che Yizhong Lu Zongming liu School of Materials Science and Engineering University of JinanJinan250022China Infovision Optoelectronics(Kunshan)Co. Ltd.Kunshan215333China

Sr_(2)NaMg_(2)V_(3)O_(12):xEu phosphors with uniform particle size/morphology and good dispersion can be synthesized via solid state *** the optimum excitation wavelength of ~340 nm,the Sr_(2)NaMg_(2)V_(3)O_(12):xEu phosphor displays the broad emission band at ~500 nm(blue-green emission,^(3)T_(1,2)→^(1)A_(1) transition of[VO_(4)]^(3-))and sharp emission peak at~610 nm(red emission,^(5)D_(0)→^(7)F_(2) transition of Eu^(3+)),*** the Eu^(3+)content increasing,the emission intensity of[VO_(4)]^(3-)decreases gradually while the emission intensity of Eu^(3+)increases,which is ascribed to the energy transfer from[VO_(4)]^(3-)to Eu^(3+)*** decay time of[VO_(4)]^(3-)(-500 nm)increases gradually with the Eu^(3+)content *** energy transfer efficiency and mechanism of[VO_(4)]^(3-)→Eu^(3+)ions were analyzed,*** emission color of Sr_(2)NaMg_(2)V_(3)O_(12):xEu phosphor was regulated from green to red via altering the Eu^(3+)ions *** is delightful for us that the white color emission can be just achieved when the Eu^(3+)content is 5 at%(x=0.05),and the w-LED can be *** studying the luminescence temperature dependence and activation energy of Sr_(2)NaMg_(2)V_3O_(12):xEu phosphor,it is shown that the phosphor has good thermal *** Sr_(2)NaMg_(2)V_3O_(12):xEu powder is expected to be a new type of phosphor widely used in light and display areas.

关键词： Phosphor W-LEDs Thermal stability Energy transfer Rare earths