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LARGE-TIME BEHAVIOR OF SOLUTIONS OF QUANTUM HYDRODYNAMIC MODEL FOR SEMICONDUCTORS 被引量:3
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作者 贾月玲 李海梁 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期163-178,共16页
A one-dimensional quantum hydrodynamic model (or quantum Euler-Poisson system) for semiconductors with initial boundary conditions is considered for general pressure-density function. The existence and uniqueness of... A one-dimensional quantum hydrodynamic model (or quantum Euler-Poisson system) for semiconductors with initial boundary conditions is considered for general pressure-density function. The existence and uniqueness of the classical solution of the corresponding steady-state quantum hydrodynamic equations is proved. Furthermore, the global existence of classical solution, when the initial datum is a perturbation of t he steadystate solution, is obtained. This solution tends to the corresponding steady-state solution exponentially fast as the time tends to infinity. 展开更多
关键词 Quantum hydrodynamic equation quantum Euler-Poisson system global existence of classical solution rlonlinear fourth-order wave equation exponential decay large-time behavior
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Large-time Behavior of Solutions to the Stokes Approximation Equations for Two Dimensional Compressible Flows 被引量:2
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作者 Zhen-hua Guo 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2005年第4期637-654,共18页
In this paper, we study the large time asymptotic behavior of solutions to both the Cauchy problem and the exterior problem of the Stokes approximation equations of two dimensional compressible flows.
关键词 large-time behavior Stokes approximation equations two dimension
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Asymptotic Behavior and Nonexistence of Positive Solutions of Delay Difference Equations
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作者 彭名书 徐千里 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期25-30,共6页
目的讨论一类带可变系数二阶非线性中立型时滞差分方程正解所具有的性质.方法通过运用差分不等式及几个常用不等式,建立了两个引理.结果与结论获得了有关此类方程正解的渐近性质及不存在正解的新准则,推广并改善了最近文献的某些结... 目的讨论一类带可变系数二阶非线性中立型时滞差分方程正解所具有的性质.方法通过运用差分不等式及几个常用不等式,建立了两个引理.结果与结论获得了有关此类方程正解的渐近性质及不存在正解的新准则,推广并改善了最近文献的某些结果,同时还给出了具体的实例,以说明结果的实用、精确和重要. 展开更多
关键词 振动 渐近性 正解 中立型时滞差分方程 非线性
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LIMITING BEHAVIOR OF BLOW-UP SOLUTIONS OF THE NLSE WITH A STARK POTENTIAL 被引量:1
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作者 朱世辉 张健 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1181-1192,共12页
This article is concerned with blow-up solutions of the Cauchy problem of critical nonlinear SchrSdinger equation with a Stark potential. By using the variational characterization of corresponding ground state, the li... This article is concerned with blow-up solutions of the Cauchy problem of critical nonlinear SchrSdinger equation with a Stark potential. By using the variational characterization of corresponding ground state, the limiting behavior of blow-up solutions with critical and small super-critical mass are obtained in the natural energy space ∑ = {u ∈ H^1; fRN |x|^2|u|^2dx 〈 +∞)}. Moreover, an interesting concentration property of the blow-up solutions with critical mass is gotten, which reads that |u(t, x)|^2→ ||Q||L^2 2 δx=x1 as t → T. 展开更多
关键词 Nonlinear Schroedinger equation Stark potential blow-up solution limiting behavior mass concentration
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Electrospinning and Rheological Behavior of Poly(vinyl alcohol)/Collagen Blended Solutions 被引量:1
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作者 张晓莉 汤克勇 ZHENG Xuejing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第4期840-846,共7页
Poly(vinyl alcohol)/collagen (PVA/COL) micro-nanofibers were successfully prepared by electrospinning process. Water, green, and non-toxic was used as the solvent. The electrospun mats consisted of micro-nanoscale... Poly(vinyl alcohol)/collagen (PVA/COL) micro-nanofibers were successfully prepared by electrospinning process. Water, green, and non-toxic was used as the solvent. The electrospun mats consisted of micro-nanoscale fibers with mean diameter ranging from approximately 363 nm to 179 nm. It was observed that the mean diameters of PVA/COL electrospun fibers decreased with increasing collagen content. The effects of PVA/COL blending ratio on the rheological behavior of PVA/COL blended solutions were investigated by rotate rheometer. It was found that PVA/COL blended solutions behaved as Non-Newtonian fluids. With increasing collagen content, the Non-Newtonian index (n) of PVA/COL blended solutions decreased. Meanwhile, a linear relationship was found between the Non-Newtonian index (n) and the mean diameters of the PVA/COL micro- nanofibers. The chemical structures of PVA/COL electrospun fibers were also characterized by FTIR. 展开更多
关键词 ELECTROSPINNING PVA/COL blended solution micro-nanofibers rheological behavior
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EXISTENCE AND ASYMPTOTIC BEHAVIOR OF THE SOLUTIONS FOR A NONLINEAR ELLIPTIC EQUATION ARISING IN ASTROPHYSICS 被引量:1
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作者 唐仲伟 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期229-245,共17页
The author first analyzes the existence of ground state solutions and cylindrically symmetric solutions and then the asymptotic behavior of the ground state solution of the equation -△u =φ(r)u^p-1, u 〉 0 in R^N,... The author first analyzes the existence of ground state solutions and cylindrically symmetric solutions and then the asymptotic behavior of the ground state solution of the equation -△u =φ(r)u^p-1, u 〉 0 in R^N, u ∈ D^1,2(R^N), where N ≥ 3, x = (x^1,z) ∈ R^K×R^N-K,2 ≤ K ≤ N,r = |x′|. It is proved that for 2(N-s)/(N-2) 〈 p 〈 2^* = 2N/(N - 2), 0 〈 s 〈 2, the above equation has a ground state solution and a cylindrically symmetric solution. For p = 2^*, the above equation does not have a ground state solution but a cylindrically symmetric.solution, and when p close to 2^*, the ground state solutions are not cylindrically symmetric. On the other hand, it is proved that as p close to 2*, the ground state solution Up has a unique maximum point xp = (x′p, Zp) and as p → 2^*, |x′p| → r0 which attains the maximum of φ on R^N. The asymptotic behavior of ground state solution Up is also given, which also deduces that the ground state solution is not cylindrically symmetric as p goes to 2^*. 展开更多
关键词 Cylindrical symmetry asymptotic behavior ground state solution
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ASYMPTOTIC BEHAVIOR OF SOLUTIONS TO THE HEAT EQUATIONS WITH NONLINEAR BOUNDARY CONDITIONS 被引量:1
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作者 汤燕斌 周笠 Omer Ali 《Acta Mathematica Scientia》 SCIE CSCD 2004年第2期307-312,共6页
The purpose of this paper is to investigate the stability and asymptotic behavior of the time-dependent solutions to a linear parabolic equation with nonlinear boundary condition in relation to their corresponding ste... The purpose of this paper is to investigate the stability and asymptotic behavior of the time-dependent solutions to a linear parabolic equation with nonlinear boundary condition in relation to their corresponding steady state solutions. Then, the above results are extended to a semilinear parabolic equation with nonlinear boundary condition by analyzing the corresponding eigenvalue problem and using the method of upper and lower solutions. 展开更多
关键词 Asymptotic behavior heat equation nonlinear boundary condition upper and lower solutions
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Rheological Behavior for Polymer Melts and Concentrated Solutions——Part Ⅶ: A Quantitative Verification for the Molecular Theory of Non-linear Viscoelasticity with Entanglement Constraints in Polymer Melts 被引量:2
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作者 Mingshi SONG, Chen ZHANG and Guixian HU Research Institute of Polymeric Materials, Beijing University of Chemical Technology, Beijing 100029, China E-mail: wangzhchen@sina.com 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第3期375-382,共8页
Based on the molecular theory of non-linear viscoelasticity with constrained entanglements in polymer melts, the material functions in simple shear flow were formulated, the theoretical relations between and shear rat... Based on the molecular theory of non-linear viscoelasticity with constrained entanglements in polymer melts, the material functions in simple shear flow were formulated, the theoretical relations between and shear rate (), and topologically constrained dimension number and a were derived. Linear viscoelastic parameters and and topologically constrained dimension number and as a function of the primary molecular weight, molecular weight between entanglements and the entanglement sites sequence distribution in polymer chain were determined. A new method for determination of viscoelastic parameters G and topologically constrained dimension number a and and molecular weight and from the shear flow measurements was proposed. It was used to determine those parameters and structures of HDPE, making a good agreement between these values and those obtained by other methods. The agreement affords a quantitative verification for the molecular theory of nonlinear viscoelasticity with constrained entanglement in polymer melts. 展开更多
关键词 Rheological behavior for Polymer Melts and Concentrated solutions A Quantitative Verification for the Molecular Theory of Non-linear Viscoelasticity with Entanglement Constraints in Polymer Melts PART
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Corrosion behavior of CuCrNiAl alloy in HCl solutions 被引量:1
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作者 于翠艳 常立民 +1 位作者 周利敏 林红岩 《中国有色金属学会会刊:英文版》 EI CSCD 2006年第1期229-233,共5页
The corrosion behavior of a CuCrNiAl alloy in HCl solutions was studied by means of metallograph, XRD, SEM/EDX and TEM methods. The results show that in low concentration of HCl solutions, Cu of CuCrNiAl alloy is more... The corrosion behavior of a CuCrNiAl alloy in HCl solutions was studied by means of metallograph, XRD, SEM/EDX and TEM methods. The results show that in low concentration of HCl solutions, Cu of CuCrNiAl alloy is more easily subject to corrsion than Cr; the dechromisation of the CuCrNiAl alloy occurs at a certain concentration of HCl solutions, at the same time Al of CuCrNiAl alloy is subject to corrosion also. The dechromisation corrosion occurs initially at the interface between Cr phase and Cu phase, then it gradually extends Cr phase until Cr phase is dissolved completely. It is also revealed that the tendency of dechromisaion of the CuCrNiAl alloy increases with the increase in concentration and temperature of HCl solutions. 展开更多
关键词 CuCrNiAl 盐酸 XRD SEM/EDX TEM 腐蚀 铜合金
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ASYMPTOTIC BEHAVIOR OF GLOBAL SMOOTH SOLUTIONS FOR BIPOLAR COMPRESSIBLE NAVIER-STOKES-MAXWELL SYSTEM FROM PLASMAS
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作者 冯跃红 王术 李新 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期955-969,共15页
This paper is concerned with the bipolar compressible Navier-Stokes-Maxwell system for plasmas. We investigated, by means of the techniques of symmetrizer and elaborate energy method, the Cauchy problem in R^3. Under ... This paper is concerned with the bipolar compressible Navier-Stokes-Maxwell system for plasmas. We investigated, by means of the techniques of symmetrizer and elaborate energy method, the Cauchy problem in R^3. Under the assumption that the initial values are close to a equilibrium solutions, we prove that the smooth solutions of this problem converge to a steady state as the time goes to the infinity. It is shown that the difference of densities of two carriers converge to the equilibrium states with the norm ||·||H^s-1, while the velocities and the electromagnetic fields converge to the equilibrium states with weaker norms than ||·||H^s-1. This phenomenon on the charge transport shows the essential difference between the unipolar Navier-Stokes-Maxwell and the bipolar Navier-Stokes-Maxwell system. 展开更多
关键词 bipolar compressible Navier-Stokes-Maxwell system PLASMAS global smooth solutions energy estimates large-time behavior
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Corrosion-wear behavior of nanocrystalline Fe88Si12 alloy in acid and alkaline solutions
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作者 Li-cai Fu Wen Qin +2 位作者 Jun Yang Wei-min Liu Ling-ping Zhou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第1期75-82,共8页
The corrosion-wear behavior of a nanocrystalline Fe_(88)Si_(12) alloy disc coupled with a Si_3N_4 ball was investigated in acid(pH 3) and alkaline(pH 9) aqueous solutions. The dry wear was also measured for re... The corrosion-wear behavior of a nanocrystalline Fe_(88)Si_(12) alloy disc coupled with a Si_3N_4 ball was investigated in acid(pH 3) and alkaline(pH 9) aqueous solutions. The dry wear was also measured for reference. The average friction coefficient of Fe_(88)Si_(12) alloy in the pH 9 solution was approximately 0.2, which was lower than those observed for Fe_(88)Si_(12) alloy in the pH 3 solution and in the case of dry wear. The fluctuation of the friction coefficient of samples subjected to the pH 9 solution also showed similar characteristics. The wear rate in the pH 9 solution slightly increased with increasing applied load. The wear rate was approximately one order of magnitude less than that in the pH 3 solution and was far lower than that in the case of dry wear, especially at high applied load. The wear traces of Fe_(88)Si_(12) alloy under different wear conditions were examined and analyzed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The results indicated that the tribo-chemical reactions that involve oxidation of the worn surface and hydrolysis of the Si_3N_4 ball in the acid solution were restricted in the pH 9 aqueous solution. Thus, water lubrication can effectively improve the wear resistance of nanocrystalline Fe_(88)Si_(12) alloy in the pH 9 aqueous solution. 展开更多
关键词 iron silicon alloys nanocrystalline alloys wear behavior CORROSION acid solutions alkaline solutions
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In situ backscattered electron imaging study of the effect of annealing on the deformation behaviors of Ni electroformed from additive-free and saccharin-containing sulfamate solutions
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作者 Kai Jiang Hiroaki Nakano +2 位作者 Satoshi Oue Tatsuya Morikawa Wen-huai Tian 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第1期114-123,共10页
The Ni samples were electroformed from additive-free(AF) and saccharin-containing(SC) sulfamate solutions, respectively. In situ backscattered electron(BSE) imaging, electron backscatter diffraction(EBSD), and electro... The Ni samples were electroformed from additive-free(AF) and saccharin-containing(SC) sulfamate solutions, respectively. In situ backscattered electron(BSE) imaging, electron backscatter diffraction(EBSD), and electron-probe microanalysis(EPMA) were used to investigate the effect of annealing on the deformation behaviors of the AF and SC samples. The results indicate that columnar grains of the as-deposited AF sample had an approximated average width of 3 μm and an approximated aspect ratio of 8. The average width of columnar grains of the as-deposited SC sample was reduced to approximately 400 nm by the addition of saccharin to the electrolyte. A few very-large grains distributed in the matrix of the SC sample after annealing. No direct evidence indicated that S segregated at the grain boundaries before or after annealing. The average value of the total elongations of the SC samples decreased from 16% to 6% after annealing, whereas that of the AF samples increased from 18% to 50%. The dislocation recovery in grain-boundary areas of the annealed AF sample was reduced, which contributed to the appearance of microvoids at the triple junctions. The incompatibility deformation between very-large grains and fine grains contributed to the brittle fracture behavior of the annealed SC Ni. 展开更多
关键词 backscattered electron imaging ANNEALING electroformed NI SULFAMATE solution deformation behaviors
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Asymptotic Behavior of the Solutions to the One-Dimensional Nonisentropic Hydrodynamic Model for Semiconductors
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作者 LI Yeping 《Wuhan University Journal of Natural Sciences》 CAS 2008年第2期141-147,共7页
In this paper, the asymptotic behavior of the global smooth solutions to the Cauchy problem for the one-dimensional nonisentropic Euler-Poisson (or full hydrodynamic) model for semiconductors, where the energy equat... In this paper, the asymptotic behavior of the global smooth solutions to the Cauchy problem for the one-dimensional nonisentropic Euler-Poisson (or full hydrodynamic) model for semiconductors, where the energy equation with non-zero thermal conductivity coefficient are contained, is discussed. The global existence of smooth solutions for the Cauchy problem with small perturbed initial data is proved. In particular, that the solutions converge to the corresponding stationary solutions exponentially fast as t → ∞ is showed. 展开更多
关键词 asymptotic behavior global smooth solutions nonisentropic hydrodynamic model SEMICONDUCTORS
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Dynamical behaviors of traveling wave solutions to a Fujimoto-Watanabe equation
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作者 温振庶 师利娟 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期162-165,共4页
We study dynamical behaviors of traveling wave solutions to a Fujimoto-Watanabe equation using the method of dynamical systems. We obtain all possible bifurcations of phase portraits of the system in different regions... We study dynamical behaviors of traveling wave solutions to a Fujimoto-Watanabe equation using the method of dynamical systems. We obtain all possible bifurcations of phase portraits of the system in different regions of the threedimensional parameter space. Then we show the required conditions to guarantee the existence of traveling wave solutions including solitary wave solutions, periodic wave solutions, kink-like(antikink-like) wave solutions, and compactons. Moreover, we present exact expressions and simulations of these traveling wave solutions. The dynamical behaviors of these new traveling wave solutions will greatly enrich the previews results and further help us understand the physical structures and analyze the propagation of nonlinear waves. 展开更多
关键词 dynamical behaviors traveling wave solutions Fujimoto-Watanabe equation bifurcations
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On the Behavior of the Positive Solutions of the System of Two Higher-Order Rational Difference Equations
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作者 Qi Wang Gengrong Zhang Linlin Fu 《Applied Mathematics》 2013年第8期1220-1225,共6页
We study the convergence of the positive solutions of the system of the following two difference equations: where K is a positive integer, the parameters?A,B,?α, β? and the initial conditions are positive real numbe... We study the convergence of the positive solutions of the system of the following two difference equations: where K is a positive integer, the parameters?A,B,?α, β? and the initial conditions are positive real numbers. Our results generalize well known results in [1,2]. 展开更多
关键词 System of Difference EQUATIONS CONVERGENCE Positive solution behavior
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LONG-TIME BEHAVIOR OF TRANSIENT SOLUTIONS FOR CELLULAR NEURAL NETWORK SYSTEMS
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作者 蒋耀林 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第3期321-326,共6页
By establishing concept an transient solutions of general nonlinear systems converging to its equilibrium set, long-time behavior of solutions for cellular neural network systems is studied. A stability condition in g... By establishing concept an transient solutions of general nonlinear systems converging to its equilibrium set, long-time behavior of solutions for cellular neural network systems is studied. A stability condition in generalized sense is obtained. This result reported has an important guide to concrete neural network designs. 展开更多
关键词 dynamic stability cellular neural network systems long-time behavior of transient solutions
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ASYMPTOTIC BEHAVIOR OF SOLUTIONS FOR THE CHAFEE-INFANTE EQUATION
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作者 黄浩川 黄锐 《Acta Mathematica Scientia》 SCIE CSCD 2020年第2期425-441,共17页
In higher dimension,there are many interesting and challenging problems about the dynamics of non-autonomous Chafee-Infante equation.This article is concerned with the asymptotic behavior of solutions for the non-auto... In higher dimension,there are many interesting and challenging problems about the dynamics of non-autonomous Chafee-Infante equation.This article is concerned with the asymptotic behavior of solutions for the non-autonomous Chafee-Infante equation∂u∂t−Δu=λ(t)(u−u3)in higher dimension,whereλ(t)∈C1[0,T]andλ(t)is a positive,periodic function.We denoteλ1 as the first eigenvalue of−Δφ=λφ,x∈Ω;φ=0,x∈∂Ω.For any spatial dimension N≥1,we prove that ifλ(t)≤λ1,then the nontrivial solutions converge to zero,namely,limt→+∞u(x,t)=0,x∈Ω;ifλ(t)>λ1 as t→+∞,then the positive solutions are"attracted"by positive periodic solutions.Specially,ifλ(t)is independent of t,then the positive solutions converge to positive solutions of−ΔU=λ(U−U^3).Furthermore,numerical simulations are presented to verify our results. 展开更多
关键词 Chafee-Infante equation asymptotic behavior periodic solutions
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Exact explicit solitary wave and periodic wave solutions and their dynamical behaviors for the Schamel–Korteweg–de Vries equation
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作者 何斌 蒙清 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期62-76,共15页
The Schamel–Korteweg–de Vries equation is investigated by the approach of dynamics.The existences of solitary wave including ω-shape solitary wave and periodic wave are proved via investigating the dynamical behavi... The Schamel–Korteweg–de Vries equation is investigated by the approach of dynamics.The existences of solitary wave including ω-shape solitary wave and periodic wave are proved via investigating the dynamical behaviors with phase space analyses.The sufficient conditions to guarantee the existences of the above solutions in different regions of the parametric space are given.All possible exact explicit parametric representations of the waves are also presented.Along with the details of the analyses,the analytical results are numerically simulated lastly. 展开更多
关键词 Schamel–Korteweg–de Vries equation dynamical behavior solitary wave solution periodic wave solution
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EXISTENCE AND CONCENTRATION BEHAVIOR OF GROUND STATE SOLUTIONS FOR A CLASS OF GENERALIZED QUASILINEAR SCHRODINGER EQUATIONS IN R^N
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作者 陈建华 黄先玖 +1 位作者 程毕陶 唐先华 《Acta Mathematica Scientia》 SCIE CSCD 2020年第5期1495-1524,共30页
In this article,we study the generalized quasilinear Schrodinger equation-div(ε^2g^2(u)▽u)+ε^2g(u)g′(u)|▽u|^2+V(x)u=K(x)|u|^p-2u,x∈R^N where A≥3,e>0,4<p<,22*,g∈C 1(R,R+),V∈C(R^N)∩L∞(R^N)has a posit... In this article,we study the generalized quasilinear Schrodinger equation-div(ε^2g^2(u)▽u)+ε^2g(u)g′(u)|▽u|^2+V(x)u=K(x)|u|^p-2u,x∈R^N where A≥3,e>0,4<p<,22*,g∈C 1(R,R+),V∈C(R^N)∩L∞(R^N)has a positive global minimum,and K∈C(R^N)∩L∞(R^N)has a positive global maximum.By using a change of variable,we obtain the existence and concentration behavior of ground state solutions for this problem and establish a phenomenon of exponential decay. 展开更多
关键词 generalized quasilinear Schrodinger equation ground state solutions EXISTENCE concentration behavior
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THE EXISTENCE AND ASYMPTOTIC BEHAVIOR OF SOLUTIONS FOR EVOLUTION EQUATIONS AND APPLICATIONS TO P. D. E.
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作者 张壮志 《Acta Mathematica Scientia》 SCIE CSCD 1991年第2期231-240,共10页
The main purpose of this paper is to discuss the existence and asymptotic behavior of solutions for [GRAPHICS] and for which the sufficient conditions of asymptotic behavior are obtained and the restriction for the ex... The main purpose of this paper is to discuss the existence and asymptotic behavior of solutions for [GRAPHICS] and for which the sufficient conditions of asymptotic behavior are obtained and the restriction for the existence is reduced. 展开更多
关键词 THE EXISTENCE AND ASYMPTOTIC behavior OF solutions FOR EVOLUTION EQUATIONS AND APPLICATIONS TO P
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