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STABILITY OF SVIR system WITH RANDOM PERTURBATIONS

International Journal of Biomathematics 2012年第4期5卷 97-111页

作者： CHAO DENG HONGJUN GAO Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical Sciences Nanjing Normal University Nanjing 210046 P. R. China

In this paper, the SVIR epidemic models with continuous vaccination strategies investi- gated by Liu, Takeuchi and Iwamo, [SVIR epidemic models with vaccination strategies, J. Theor. Biol. 253 （2008） 1 11], allowing random fluctuation around the endemic equi- librium and the transmission rate t3 are analyzed. The equilibrium state of the model with random perturbation is locally asymptotically stable as shown by a Lyapunov stability analysis.

关键词： Local asymptotic stability SVIR model Lyapunov function white noise.

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Analysis of a mutualism model with stochastic perturbations

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International Journal of Biomathematics 2015年第6期8卷 19-36页

作者： Mei Li Hongjun Gao Chenfeng Sun Yuezheng Gong Institute of Mathematics Nanjing Normal University Nanjing 210023 P. R. China School of Applied MathematicsNanjing University of Finance and Economics Nanjing 210023 P. R. China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex SystemsNanjing Normal University Nanjing 210023 P. R. China

This paper is concerned with a mutualism ecological model with stochastic perturba- tions. The local existence and uniqueness of a positive solution are obtained with positive initial value, and the asymptotic behavior to the problem is studied. Moreover, we show that the solution is stochastically bounded, uniformly continuous and stochastic perma- nence. The sufficient conditions for the system to be extinct are given and the conditionsfor the system to be persistent are also established. At last, some figures are presented to illustrate our main results.

关键词： Ito＇s formula mutualism model persistent in mean extinction uniformlycontinuous.

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Ru-Ni alloy nanosheets as tandem catalysts for electrochemical reduction of nitrate to ammonia

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Nano Research 2024年第6期17卷 4815-4824页

作者： Xingchao You Jiawei Xu Zechao Zhuang Junkai Xia Suwen Wang Haiyan Wei Yongfu Li Yanjiang Cai Hai Xiang Bing Yu State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Ecological-Environment&Health College(EEHC) Zhejiang A&F UniversityHangzhou 311300China Jiangsu Key Laboratory of Numerical Simulation of Large Scale Complex Systems and School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Department of Chemistry Tsinghua UniversityBeijing 100084China Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA

Developing electrocatalysts that exhibit both high activity and ammonia selectivity for nitrate reduction is a significant and demanding challenge,primarily due to the complex nature of the multiple-electron reduction process *** encouraging approach involves coupling highly active precious metals with transition metals to enhance catalytic performance through ***,we report a ruthenium-nickel alloy catalyst with nanosheets(Ru-Ni NSs)structure that achieves a remarkable ammonia Faradaic efficiency of approximately 95.93%,alongside a yield rate of up to 6.11 g·h^(−1)·cm^(−2).Moreover,the prepared Ru-Ni NSs exhibit exceptional stability during continuous nitrate reduction in a flow reactor for 100 h,maintaining a Faradaic efficiency of approximately 90%and an ammonia yield of 37.4 mg·L^(−1)·h^(−1)using 0.05 M nitrate alkaline *** studies reveal that the catalytic process follows a two-step pathway,in which HONO serves as a migration *** presence of a partially oxidized Ru(002)surface enhances the adsorption of nitrate and facilitates the release of the migration intermediate by adjusting the strength of the electrostatic and covalent interactions between the adsorbate and the surface,*** the other hand,the Ni(111)surface promotes the utilization of the migration intermediate and requires less energy for NH_(3)*** tandem process contributes to a high catalytic activity of Ru-Ni NSs towards nitrate reduction.

关键词： alloy catalyst nitrate reduction ammonia synthesis Faradaic efficiency

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Delocalizedπ_(3)^(6) Bond in OX_(2) (X=Halogen) Molecules

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Chinese Journal of Chemical Physics 2022年第3期35卷 542-550,I0003页

作者： Yi-han Tang Pu Yang Meng-yuan Chen Yu-ru Wang Jia-xin Wang Jia-wei Xu School of Petrochemical Engineering Changzhou UniversityChangzhou 213164China Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Key Laboratory of Numerical Simulation of Large Scale Complex System Nanjing Normal UniversityNanjing 210023China

OX_(2)(X=halogen)molecules was studied *** results show that delocalizedπ_(3)^(6) bonds exist in their electronic structures and O atoms adopt the sp^(2) type of hybridization,which violates the prediction of the valence shell electron pair repulsion theory of sp^(3) *** stabilization energy is proposed to measure the contribution of delocalizedπ_(3)^(6) bond to energy decrease and proves to bring extra-stability to the *** phenomena can be summarized as a kind of coordinating effect.

关键词： Theoretical and computational chemistry Valence shell electron pair repulsion theory Delocalizedπbond Delocalization stabilization energy Dihalogen monoxide

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The qqsQ(q=u,d;Q=c,b)tetraquark system in a chiral quark model

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Chinese Physics C 2024年第7期48卷 84-105页

作者：杨刚平加伦 Jorge Segovia Department of Physics Zhejiang Normal UniversityJinhua 321004China Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal UniversityNanjing 210023China Departamento de Sistemas Físicos Químicos y NaturalesUniversidad Pablo de OlavideE-41013 SevillaSpain

The S-wave qqsQ(q=u,d;Q=c,b)tetraquarks,with spin-paritiesJ^(P)=0^(+),1^(+),and 2^(+),in both isoscalar and isovector sectors,are systematically studied using a chiral quark *** meson-meson,diquark-antidiquark,and K-type arrangements of quarks and all possible color wave functions are comprehensively *** four-body system is solved using the Gaussian expansion method,a highly efficient computational ***,a complex-scaling formulation of the problem is established to disentangle bound,resonance,and scattering *** theoretical framework has already been successfully applied in various tetra-and penta-quark *** the complete coupled channel and within the complex-range formulation,several narrow resonances of qqsC and qqsb systems are obtained,in each allowed I(J^(P))-channel,within the energy regions of 2.4-3.4 GeV and 5.7-6.7GeV,*** predicted exotic states,which indicate a richer color structure when going towards multiquark systems beyond mesons and baryons,are expected to be confirmed in future high-energy particle and nuclear experiments.

关键词： quantum chromodynamics quark models

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Investigation of csc¯s¯ tetraquark in the chiral quark model

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Physical Review D 2019年第9期99卷 094032-094032页

作者： Yifan Yang Jialun Ping Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 People's Republic of China

Inspired by the recent observation of exotic resonances X(4140), X(4274), X(4350), X(4500), and X(4700) reported by several experiment collaborations, we investigated the four-quark system csc¯s¯ with quantum numbers JPC=1++ and 0++ in the framework of the chiral quark model. Two configurations, diquark-antidiquark and meson-meson, with all possible color structures are considered. The results show that no molecular state can be formed, but the resonance may exist if the color structure of the meson-meson configuration is 8⊗8. In the present calculation, the X(4274) can be assigned as the csc¯s¯ tetraquark states with JPC=1++, but the energy of X(4140) is too low to be regarded as the tetraquark state. X(4350) can be a good candidate of the compact tetraquark state with JPC=0++. When the radial excitation is taken into account, the X(4700) can be explained as the 2S radial excited tetraquark state with JPC=0++. As for X(4500), there is no matching state in our calculation.

关键词： Hadron-hadron interactions Quark model

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Investigation of qqqsq¯ pentaquarks in a chiral quark model

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Physical Review C 2021年第1期103卷 015203-015203页

作者： Liting Qin Yue Tan Xiaohuang Hu Jialun Ping Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 People's Republic of China

We investigate the pentaquark system qqqsq¯ in a framework of chiral quark model. Two structures, (qqq)(sq¯) and (qqs)(qq¯), with all possible color, spin, flavor configurations are considered. The calculations show that there are several possible resonance states, Σπ and NK¯ state with IJP=012−, Σ*π with IJP=032−, Σ*ρ with IJP=052−, ΔK¯ with IJP=132−, and ΔK¯* with IJP=152−. Where the NK¯ state with IJP=012− can be used to explain the Λ(1405), and together with another state Σπ is related to the two-pole structure of the scattering amplitude proposed before. The decay properties of Λ(1520) prevent the assignment of Σ*π with IJP=032− to Λ(1520), although the energy ≈1518MeV of Σ*π is close to experimental value of Λ(1520). Other resonance states generally have a large width.

关键词： Few-body systems Quark model Exotic baryons

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Y(4626) in a chiral constituent quark model

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Physical Review D 2020年第5期101卷 054010-054010页

作者： Yue Tan Jialun Ping Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 People's Republic of China

Recently, the Belle Collaboration reported a new exotic state Y(4620) with mass at 4625.9 MeV in the positronium annihilation process. Inspired by experiment, we study the tetraquark system cs¯sc¯ with quantum numbers JP=1− in the framework of chiral constituent quark model with the help of Gaussian expansion method. Two structures, diquark-antidiquark and meson-meson, with all possible color and spin configurations are considered. The result shows that no bound state can be formed. To investigate the possible resonance states, the real scaling method is employed. Several resonance states with energies 4354, 4408, 4469, 4497, and 4531 MeV are proposed. Taking into account the errors in calculating the qq¯ mesons, the system errors in the calculation of four-quark system are around 60–100 MeV. The resonance with energy 4531 MeV is possible the candidate of the newly found state Y(4620).

关键词： Hadron-hadron interactions Quark model

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Investigate the pentaquark resonance in the NK system

arXiv

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arXiv 2019年

作者： Liu, Xuejie Huang, Hongxia Ping, Jialun Department of Physics Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

A dynamical calculation of pentaquark systems with quark contents uudds¯ is performed in the framework of quark delocalization color screening model with the help of resonating group method. The effective potentials between baryon and meson clusters are given, and the possible bound states or resonances are investigated. The single calculations show that the NK∗ with (Formula presented), ∆K∗ with (Formula presented), and ∆K∗ with (Formula presented) are all bound, but they all turns into scattering states by coupling with the corresponding open channels. A possible resonance state ∆K∗ with (Formula presented) is proposed. The mass is around 2110.5 MeV, and the decay modes are NK in D-wave or NKππ in P -waves. Copyright © 2019, The Authors. All rights reserved.

关键词： Hadrons

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Investigation of the pentaquark resonance in the NK system

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Physical Review C 2019年第2期100卷 025203-025203页

作者： Xuejie Liu Hongxia Huang Jialun Ping Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 People's Republic of China

A dynamical calculation of pentaquark systems with quark contents uudds¯ is performed in the framework of a quark delocalization color screening model with the help of the resonating group method. The effective potentials between baryon and meson clusters are given, and the possible bound states or resonances are investigated. The single calculations show that the NK* with I=0,JP=12−,ΔK* with I=1,JP=12−, and ΔK* with I=2,JP=32− are all bound, but they all turn into scattering states by coupling with the corresponding open channels. A possible resonance state ΔK* with I=1,JP=52− is proposed. The mass is around 2110.5 MeV, and the decay modes are NK in D wave and NKππ in P waves.

关键词： Hadron-hadron interactions Quark model Exotic baryons

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