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Quantum Dynamics of Li+HF/DF Reaction Investigated by a State-to-State Time-dependent Wave Packet Approach

Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： Wen-tao Li mao-du chen Zhi-gang Sun School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024ChinaState Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024China State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

Using the reactant coordinate based time-dependent wave packet method, on the APW po- tential energy surface, the differential and integral cross sections of the Li+DF/HF(v=0, j=0, 1) reactions were calculated over the collision energy range from the threshold to 0.25 eV. The initial state-specified reaction rate constants of the title reaction were also calculated. The results indicate that, compared with the Li+DF reaction, the product LiF of Li+HF reaction is a little more rotationally excited but essentially similar. The initial rotational excitation from j=0 to 1 has little effect on the Li+DF reaction. However, the rotational excitation of DF does result in a little more rotationally excited product LiF. The different cross section of both reactions is forward biased in the studied collision energy range, especially at relatively high collision energy. The resonances in the Li+HF reaction may be identifiable as the oscillations in the product ro-vibrational state-resolved integral cross sections and backward scattering as a function of collusion energy. For the Li+HF reaction, the rate constant is not sensitive to the temperature and almost has no change in the temperature range considered. For the Li+DF reaction, the rate constant increase by a factor of about 10 in the temperature range of 100?300 K. Brief comparison for the total reaction probabilities and integral cross section of the Li+HF reaction has been carried out between ours and the values reported previously. The agreement is good, and the difference should come from the better convergence of our present calculations.

关键词： Quantum wavepacket Integral and differential cross section Reaction rate constant Li+HF/DF Isotope effect

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Current neutralization and plasma polarization for intense ion beams propagating through magnetized background plasmas in a two-dimensional slab approximation

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Frontiers of physics 2014年第2期9卷 226-233页

作者： Zhang-Hu Hu mao-du chen You-Nian Wang School of Physics and Optoeleetronic Technology Dalian University of Technology Dalian 116024 China

A two-dimensional electromagnetic Particle-in-Cell （PIC） simulation model is proposed to study the propagation of intense, ion beams with beaIn width wb small compared to the electron skin depth c/wpe through background plaslnas in tile presence of external applied magnetic fields. The effcctive eleetron gyrora,dius wge is found to be an important parameter for ion beam transport in the presence of magnetic fields,In the bealn regions, the background plasmas respond differently to the ion beanl of width wb〈wge and wb 〉 wge for the given magnetic field and beaan encrgy, For the case of beam width wb 〈 wge with relative weak external magnetic fiehts, the rotalion effects of plasma electrons a,re found to be signifieant and contributes to the signitica,nt enilaneeinent of the self electric and seif-magnetic fields. While for the ease of beam width wb 〉 wge with relative strong external magnetic fields, the rotation effects of plasma cleetrons are strongly inhibited and a, well neutraliza, tion of ion beam current can be found. Finally, the influences of diftiuent beam widths. beam energies and magnetic fields on the neutralization of ion bc, anl eurrellt are summarized for the eases of wb 〈 wge〈 c/wpe,wge 〈wb〈c/wbp and wb〈c/wpe〈wge.

关键词： current neutralization ion beams magnetized plasmas Particle-in-Cell simulations

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Transition Dipole, Charge Transfer, and Electron-hole Coherence in Two-photon Absorption： Visualizations with Two Dimensional Site and Three Dimensional Cube Representations

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Chinese Journal of Chemical Physics 2009年第5期22卷 529-534,I0002页

作者： Yuan-zuo Li Wen-qin Zhang Xiao-hong Zhao Feng-cai Ma mao-du chen School of Physics and Optoelectronic Technology and College of Advanced Science and Technology Dalian University of Technology Dalian 116024 China Department of Physics Liaoning University Shenyang 110036 China

The developed visualization methods of two dimensional （2D） site and three dimensional （3D） cube representations have been performed to show the orientation of transition dipole, charge transfer, and electron-hole coherence in two-photon absorption （TPA）. The 3D cube representations of transition density can reveal visually the orientation and strength of transition dipole moment, and charge different density show the orientation of charge transfer in TPA. The 2D site representation can reveal visually the electron-hole coherence in TPA. The combination of 2D site and 3D cube representations provide clearly inspect into the charge transfer process and the contribution of excited molecular segments for TPA.

关键词： 2D site and 3D cube representations Charge transfer Transition dipole,Two-photon absorption

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Suppression of Photoinduced BBO Defects Generation on TIO2（110） by Water

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Chinese Journal of Chemical Physics 2013年第6期26卷 646-650,I0003页

作者： chen-biao Xu Wen-shao Yang Qing Guo Dong-xu Dai mao-du chen Xue-ming Yang School of Physics and Optoelectronic Engineering Dalian University of Technology Dalian 116024China State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Dalian 116023 China

We have investigated creation of variable concentrations of defects on TIO2（110）-（1×1） surface by 266 nm laser using temperature programmed desorption technique. Oxygen-vacancy defects can be easily induced by ultraviolet light, the defects concentration has a linear dependence on power density higher than 50 mW/cm2 for 90 s irradiation. No observation of O2 molecule and Ti atom desorption suggests that UV induced defects creation on TiO2（110）-（1×1） is an effective and gentle method. With pre-dosage of thin films of water, the rate of defects creation on TiO2（110）-（1×1） is slower at least by two orders of magnitude than bare TiO2（110）-（1×1） surface. Further investigations show that water can be more easily desorbed by UV light, and thus desorption of bridging oxygen is depressed.

关键词： Temperature programmed desorption Time of flight spectrum Photo- stimulated desorption Oxygen vacancy

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Non-adiabatic quantum dynamical studies of Na(3p) + HD(v = 1, j5) = 0)→NaH/NaD + D/H reaction

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Chinese Physics B 2019年第6期28卷 169-175页

作者： Yue-Pei Wen Bayaer Buren mao-du chen Key Laboratory of Materials Modification by Laser Electronand Ion Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China

Non-adiabatic dynamical calculations are carried out for the Na(3 p)+HD(ν = 1, j = 0)→NaH/NaD+D/H reaction on the diabatic potential energy surfaces of Wang et al.(Sci. Rep. 2018, 8, 17960) by using the time-dependent wave packet method. The state-to-state integral cross sections and differential cross sections of two reaction channels(NaH/NaD+D/H)are calculated for collision energy up to 0.4 eV. The cross section branching ratio indicates that the dominant reaction channel changes from NaD+H to NaH+D when the collision energy is larger than 0.227 eV. The products from two reaction channels both prefer to form in vibrationally cold but rotationally hot states, and they both tend to forward scattering.

关键词： time-dependent wave packet method non-adiabatic reaction integral cross section differential cross section

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The mid-domain effect in flowering phenology

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Plant Diversity 2024年第4期46卷 502-509页

作者： Yanjun du Rongchen Zhang Xinran Tang Xinyang Wang Lingfeng mao Guoke chen Jiangshan Lai Keping Ma School of Tropical Agriculture and Forestry(School of Agricultural and Rural Affairs School of Rural Revitalization)Hainan UniversityHaikou 570228China HNU-ASU Joint International Tourism College Hainan UniversityHaikou 570228China School of Ecological and Environmental Sciences East China Normal UniversityShanghai 200062China College of Ecology and Environment Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

The timing of flowering is an important driver of species distribution and community assembly ***,we still have much to learn about the factors that shape flowering diversity(i.e.,number of species flowering per period) in plant *** potential explanation of flowering diversity is the mid-domain effect,which states that geometric constraints on species ranges within a bounded domain(space or time) will yield a mid-domain peak in diversity regardless of ecological ***,we determine whether the mid-domain effect explains peak flowering time(i.e.,when most species of communities are flowering) across *** used phenological data of 16,267 herbaceous and woody species from the provincial Flora in China and species distribution data from the Chinese Vascular Plant Distribution Database to determine relationships between the observed number of species flowering and the number of species flowering as predicted by the mid-domain effect model,as well as between three climatic variables(mean minimum monthly temperature,mean monthly precipitation,and mean monthly sunshine duration).We found that the mid-domain effect explained a significant proportion of the temporal variation in flowering diversity across all species in ***,the mid-domain effect explained a greater proportion of variance in flowering diversity at higher latitudes than at lower *** patterns of flowering diversity for both herbaceous and woody species were related to both the mid-domain effect and environmental *** findings indicate that including geometric constraints in conjunction with abiotic and biotic predictors will improve predictions of flowering diversity patterns.

关键词： Flowering diversity Functional biogeography Latitudinal gradient Macroecology Macrophenology Null model

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Equilibrium Strategy of the Pursuit-Evasion Game in Three-Dimensional Space

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 446-458页

作者： Nuo chen Linjing Li Wenji mao School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049 Institute of Automation Chinese Academy of SciencesBeijing 100190China

The pursuit-evasion game models the strategic interaction among players, attracting attention in many realistic scenarios, such as missile guidance, unmanned aerial vehicles, and target defense. Existing studies mainly concentrate on the cooperative pursuit of multiple players in two-dimensional pursuit-evasion games. However, these approaches can hardly be applied to practical situations where players usually move in three-dimensional space with a three-degree-of-freedom control. In this paper,we make the first attempt to investigate the equilibrium strategy of the realistic pursuit-evasion game, in which the pursuer follows a three-degree-of-freedom control, and the evader moves freely. First, we describe the pursuer's three-degree-of-freedom control and the evader's relative coordinate. We then rigorously derive the equilibrium strategy by solving the retrogressive path equation according to the Hamilton-Jacobi-Bellman-Isaacs(HJBI) method, which divides the pursuit-evasion process into the navigation and acceleration phases. Besides, we analyze the maximum allowable speed for the pursuer to capture the evader successfully and provide the strategy with which the evader can escape when the pursuer's speed exceeds the threshold. We further conduct comparison tests with various unilateral deviations to verify that the proposed strategy forms a Nash equilibrium.

关键词： Differential game equilibrium strategy pursuit-evasion game threedegree-of-freedom control

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Impacts of information about COVID-19 on pig farmers'production willingness and behavior:Evidence from China

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Journal of Integrative Agriculture 2024年第4期23卷 1429-1441页

作者： Huan chen Lei mao Yuehua Zhang School of Public Affairs Zhejiang UniversityHangzhou 310058China School of Insurance Central University of Finance and EconomicsBeijing 100081China Innovation Center of Yangtze River Delta Zhejiang UniversityJiaxing 314100China

This paper examines the impacts of information about COVID-19 on pig farmers'production willingness by using endorsement experiments and follow-up surveys conducted in 2020 and 2021 in *** results show that,first,farmers were less willing to scale up production when they received information about *** information in 2020 that the second wave of COVID-19 might occur without a vaccine reduced farmers'willingness to scale up by 13.4%,while the information in 2021 that COVID-19 might continue to spread despite the introduction of vaccine reduced farmers'willingness by 4.4%.Second,farmers whose production was affected by COVID-19 were considerably less willing to scale up,given the access to COVID-19 ***,farmers'production willingness can predict their actual production behavior.

关键词： COVID-19 randomized experiment information treatment production willingness

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Parametric resonance of axially functionally graded pipes conveying pulsating fluid

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 239-260页

作者： Jie JING Xiaoye mao Hu DING Liqun chen Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Based on the generalized Hamilton's principle,the nonlinear governing equation of an axially functionally graded(AFG)pipe is *** non-trivial equilibrium configuration is superposed by the modal functions of a simply supported *** the direct multi-scale method,the response and stability boundary to the pulsating fluid velocity are solved analytically and verified by the differential quadrature element method(DQEM).The influence of Young's modulus gradient on the parametric resonance is investigated in the subcritical and supercritical *** general,the pipe in the supercritical region is more sensitive to the pulsating *** nonlinearity changes from hard to soft,and the non-trivial equilibrium configuration introduces more frequency components to the ***,the increasing Young's modulus gradient improves the critical pulsating flow velocity of the parametric resonance,and further enhances the stability of the *** addition,when the temperature increases along the axial direction,reducing the gradient parameter can enhance the response *** work further complements the theoretical analysis of pipes conveying pulsating fluid.

关键词： pipe conveying fluid axially functionally graded supercritical resonance multi-scale method parametric resonance

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Dynamic steric confinement effect expands the frontier of Cu-catalyzed asymmetric propargylic aminations

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Science China Chemistry 2024年第10期67卷 3181-3183页

作者： Peng chen mao-mao Zhang Wen-Jing Xiao Liang-Qiu Lu Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University Wuhan Institute of Photochemistry and Technology State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics (LICP)Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Chiral α-tertiary amines and related azacycles are commonly found in many natural products, pharmaceuticals and agrochemicals [1]. Copper-catalyzed asymmetric propargylic amination(APA) reactions have been established as a reliable method to access enantio-enriched propargylic amines,largely due to the seminal contribution of Nishibayashi et al.[2] and van Maarseveen et al. [3] in 2008.

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