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非平衡相变的临界标度理论及普适性 被引量:11
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作者 蔡绍洪 戴陵江 +1 位作者 胡林 李坚石 《物理学进展》 CSCD 北大核心 1999年第3期270-304,共35页
综述了作者近年来在非平衡相变临界( N P C) 标度理论及普适性研究的进展。主要包括一般 N P C 系统规格化模型,局域序参量的概率分布,广义势的临界渐近形式,空时有关函数及其临界奇异行为。论证了 N P C 系统的临界可... 综述了作者近年来在非平衡相变临界( N P C) 标度理论及普适性研究的进展。主要包括一般 N P C 系统规格化模型,局域序参量的概率分布,广义势的临界渐近形式,空时有关函数及其临界奇异行为。论证了 N P C 系统的临界可标度性,导出了一组普适的 N P C 标度关系,由之计算出的4 种 N P C 普适类的临界指数与目前已知的实验及理论结果吻合得非常好。此外,还讨论了非平衡相变临界标度理论的普适性,将平衡相变临界标度理论作为一种特殊极限情况含于同一理论体系中。 展开更多
关键词 非平衡相变 临界现象 NPC 标度关系 临界指数
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全空间上具有临界指数的Kirchhoff类方程无穷多个正解的存在性 被引量:11
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作者 丁凌 汪继秀 肖氏武 《南昌大学学报(理科版)》 CAS 北大核心 2017年第5期414-417,共4页
研究了全空间上具有临界指数的广义的非线性Kirchhoff类方程,在给定参数和空间维数的不同范围内,用各种分析技巧,得到了方程无穷多个正解的存在性结果。
关键词 Kirchhoff类方程 临界指数 最优常数
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Critical exponents of degenerate parabolic equations 被引量:4
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作者 齐远伟 《Science China Mathematics》 SCIE 1995年第10期1153-1162,共10页
The Cauchy problem in Rn of (i) ut = Δuα+1+uβ and (ii) with non-negative initial value is studied. Here α>0, β>1. It is proved that for (i) with β = α+2/n being the critical case every non-trivial solutio... The Cauchy problem in Rn of (i) ut = Δuα+1+uβ and (ii) with non-negative initial value is studied. Here α>0, β>1. It is proved that for (i) with β = α+2/n being the critical case every non-trivial solution blows up in finite time. A similar result is proved for (ii). 展开更多
关键词 critical exponents DEGENERATE EQUATIONS CAUCHY problem MAXIMUM principles.
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一类非局部反应扩散方程组Cauchy问题的临界爆破指标 被引量:4
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作者 张丽琴 《数学研究》 CSCD 2001年第2期136-141,共6页
证明了一类来源于燃烧理论的非局部反应扩散方程组Cauchy问题解的局部存在性、唯一性及临界爆破指标的存在性 .并证明临界爆破指标属于爆破情形 .
关键词 非局部反应扩散方程组 整体解 临界爆破指标 CAUCHY问题 燃烧理论 比较原理
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全空间上具有临界指数的Kirchhoff类方程两个正解的存在性 被引量:5
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作者 丁凌 汪继秀 张丹丹 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第3期457-461,共5页
本文在参数的不同范围及给定假设下利用Ekeland变分原理、山路引理、集中紧性原理和一些分析技巧得到了全空间上具有临界指数的非线性项和非齐次扰动项的Kirchhoff类方程两个正解的存在性.
关键词 Kirchhoff类方程 临界指数 EKELAND变分原理 山路引理 集中紧性原理
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具有非局部边界的退化抛物方程组的爆破解 被引量:4
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作者 杨婕 刘丙辰 张长城 《数学杂志》 北大核心 2017年第6期1275-1286,共12页
本文研究了具有非局部边界条件和非局部源的退化抛物方程组的弱解问题.利用基于比较原理的上下解的方法,在权函数和初始条件的假设下,获得了该方程组问题的爆破临界指标.此外,还获得了同时爆破解趋于爆破时间时的渐近行为,推广了已有的... 本文研究了具有非局部边界条件和非局部源的退化抛物方程组的弱解问题.利用基于比较原理的上下解的方法,在权函数和初始条件的假设下,获得了该方程组问题的爆破临界指标.此外,还获得了同时爆破解趋于爆破时间时的渐近行为,推广了已有的结果. 展开更多
关键词 退化抛物方程组 临界指标 渐近行为 非局部边界
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Computational study of inverse ferrite spinels 被引量:1
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作者 A EL Maazouzi R Masrour +1 位作者 A Jabar M Hamedoun 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期305-311,共7页
The magnetic properties of inverse ferrite Fe_(3+) Fe_(3+)Co_(2+) O^(2-)_4, Fe^(3+) Fe^(3+)Cu^(2+) O^2_(-4), Fe^(3+) Fe^(3+)Fe^(2+) O^2_(-4),and Fe^(3+) Fe^(3+)Ni^(2+) O^(2-)_4spinels have been studied using Monte Car... The magnetic properties of inverse ferrite Fe_(3+) Fe_(3+)Co_(2+) O^(2-)_4, Fe^(3+) Fe^(3+)Cu^(2+) O^2_(-4), Fe^(3+) Fe^(3+)Fe^(2+) O^2_(-4),and Fe^(3+) Fe^(3+)Ni^(2+) O^(2-)_4spinels have been studied using Monte Carlo simulation. We have also calculated the critical and Curie Weiss temperatures from the thermal magnetizations and inverse of magnetic susceptibilities for each system.Magnetic hysteresis cycles have been found for the four systems. Finally, we found the critical exponents associated with magnetization, magnetic susceptibility, and external magnetic field. Our results of critical and Curie Weiss temperatures are similar to those obtained by experiment results. The critical exponents are similar to those of known 3 D-Ising model. 展开更多
关键词 INVERSE ferrites SPINELS Monte Carlo simulation critical and CURIE Weiss TEMPERATURES magnetic hysteresis cycles critical exponents
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p-LAPLACE EQUATIONS WITH MULTIPLE CRITICAL EXPONENTS AND SINGULAR CYLINDRICAL POTENTIAL 被引量:2
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作者 孙小妹 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1099-1112,共14页
In this paper, we deal with the following problem:By variational method, we prove the existenceof a nontrivial weak solution whenand the existence of a cylindricalweak solution when
关键词 p-Laplace equation cylindrical potential critical exponents
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Ising模型集团大小对重正化结果影响的分析 被引量:3
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作者 王宗笠 李晓寒 《安徽大学学报(自然科学版)》 CAS 北大核心 2005年第4期50-53,共4页
以二维三角晶格为例选取包含9个晶格的晶胞为Kadanoff集团,通过重正化变换求出其临界点和临界指数并与三角晶格[1]、六角晶格[2]的结果作比较,比较的结果表明:选取更大的集团可以提高其计算精度。
关键词 重正化群变换 Kadanoff集团 临界点 临界指数
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一类奇异双调和方程变号解的存在性 被引量:3
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作者 杜刚 魏静 《数学的实践与认识》 CSCD 北大核心 2011年第23期172-177,共6页
讨论了一类具有奇异系数的双调和问题其中N≥5:Ω是R^N中一有界光滑区域,0∈Ω,2~*(s)=2(N-s)/(n-4),0≤s≤4,2<q<2~*,2~*=2N/(N-4),0<μ<μ=[N(N-4)/4]~2,λ>0.利用一个新的环绕定理,讨论了该问题变号解的存在性.
关键词 双调和方程 临界指数 变号解 环绕
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LOCATION OF THE BLOW UP POINT FOR POSITIVE SOLUTIONS OF A BIHARMONIC EQUATION INVOLVING NEARLY CRITICAL EXPONENT 被引量:1
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作者 耿堤 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期283-295,共13页
In this paper a semilinear biharmonic problem involving nearly critical growth with Navier boundary condition is considered on an any bounded smooth domain. It is proved that positive solutions concentrate on a point ... In this paper a semilinear biharmonic problem involving nearly critical growth with Navier boundary condition is considered on an any bounded smooth domain. It is proved that positive solutions concentrate on a point in the domain, which is also a critical point of the Robin’s function corresponding to the Green’s function of biharmonic operator with the same boundary condition. Similar conclusion has been obtained in [6] under the condition that the domain is strictly convex. 展开更多
关键词 Biharmonic operator Navier boundary conditions asymptotic behavior critical exponents Green's function
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Some Applications of the Percolation Theory: Brief Review of the Century Beginning 被引量:2
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作者 Alexander Herega 《材料科学与工程(中英文A版)》 2015年第11期409-414,共6页
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Universality Class of the Nonequilibrium Phase Transition in Two-Dimensional Ising Ferromagnet Driven by Propagating Magnetic Field Wave
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作者 Ajay Halder Muktish Acharyya 《Applied Mathematics》 2019年第7期568-577,共10页
The purpose of this work is to identify the universality class of the nonequilibrium phase transition in the two-dimensional kinetic Ising ferromagnet driven by propagating magnetic field wave. To address this issue, ... The purpose of this work is to identify the universality class of the nonequilibrium phase transition in the two-dimensional kinetic Ising ferromagnet driven by propagating magnetic field wave. To address this issue, the finite size analysis of the nonequilibrium phase transition, in two-dimensional Ising ferromagnet driven by plane propagating magnetic wave, is studied by Monte Carlo simulation. It is observed that the system undergoes a nonequilibrium dynamic phase transition from a high temperature dynamically symmetric (propagating) phase to a low temperature dynamically symmetry-broken (pinned) phase as the system is cooled below the transition temperature. This transition temperature is determined precisely by studying the fourth-order Binder Cumulant of the dynamic order parameter as a function of temperature for different system sizes (L). From the finite size analysis of dynamic order parameter ?and the dynamic susceptibility , we have estimated the critical exponents and ?(measured from the data read at the critical temperature obtained from Binder cumulant), and (measured from the peak positions of dynamic susceptibility). Our results indicate that such driven Ising ferromagnet belongs to the same universality class of the two-dimensional equilibrium Ising ferromagnet (where and ), within the limits of statistical errors. 展开更多
关键词 ISING Model Dynamic Phase Transition Monte-Carlo Simulation PROPAGATING WAVE FINITE Size Analysis critical exponents UNIVERSALITY
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ASYMPTOTICS FOR POSITIVE SOLUTIONS OF THE WEIGHTED LAPLACE EQUATIONS INVOLVINGCRITICAL GROWTH
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作者 耿堤 《Acta Mathematica Scientia》 SCIE CSCD 2000年第1期12-18,共7页
A general weighted second order elliptic equation involving critical growth is considered on bounded smooth. domain in n-dimension space. There is the singular point for the weighted coefficients in the domain. With g... A general weighted second order elliptic equation involving critical growth is considered on bounded smooth. domain in n-dimension space. There is the singular point for the weighted coefficients in the domain. With generalized blow up method, some results are obtained for asymptotic behavior of positive solutions. This problem includes Laplacian operators as special cases. 展开更多
关键词 weighed Laplace operator asymptotic behavior critical exponents the Green's function
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MULTIPLE NONTRIVIAL SOLUTIONS FOR A CLASS OF SEMILINEAR POLYHARMONIC EQUATIONS
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作者 尚月赟 王莉 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1495-1509,共15页
In this paper, we are concerned with the following problem:{(-△)ku=λf(x)|u|q-2u+g(x)|u|k*-2u, x∈Ω, u∈H k0 (Ω), where Ωis a bounded domain in RN with N ≥2k+1, 1〈q〈2,λ〉0, f, g are continuous ... In this paper, we are concerned with the following problem:{(-△)ku=λf(x)|u|q-2u+g(x)|u|k*-2u, x∈Ω, u∈H k0 (Ω), where Ωis a bounded domain in RN with N ≥2k+1, 1〈q〈2,λ〉0, f, g are continuous functions on Ω which are somewhere positive but which may change sign on Ω. k* = N2/N-2k is the critical Sobolev exponent. By extracting the Palais-Smale sequence in the Nehari manifold, the existence of multiple nontrivial solutions to this equation is verified. 展开更多
关键词 nontrivial solutions polyharmonic problems critical exponents variationalmethods
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Finite-Size Scaling Analysis of a Three-Dimensional Blume-Capel Model in the Presence of External Magnetic Field
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作者 H. Demirel A. Ozkan B. Kutlu 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第7期2599-2602,共4页
The Blume-Capel model in the presence of external magnetic field H has been simulated using a cellular automaton algorithm improved from the Creutz cellular automaton in three-dimension lattice. The field critical exp... The Blume-Capel model in the presence of external magnetic field H has been simulated using a cellular automaton algorithm improved from the Creutz cellular automaton in three-dimension lattice. The field critical exponent 5 is estimated using the power law relations and the finite size scaling functions for the magnetization and the susceptibility in the range -0.1≤ h = H/J ≤0. The estimated value of the field critical exponent 5 is in good agreement with the universal value (δ = 5) in three dimensions. The simulations are carried out on a simple cubic lattice under periodic boundary conditions. 展开更多
关键词 2-DIMENSIONAL ISING-MODEL CREUTZ CELLULAR-AUTOMATON EMERY-GRIFFITHS MODEL TRIcritical BEHAVIOR MONTE-CARLO critical exponents PHASE-TRANSITIONS O(4) MODEL SIMULATION ANISOTROPY
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Critical exponents of ferroelectric transitions in modulated SrTiO_3:Consequences of quantum fluctuations and quenched disorder
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作者 王景雪 刘美风 +1 位作者 颜志波 刘俊明 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期516-526,共11页
The ferroelectric transitions of several SrTiO3-based ferroelectrics are investigated experimentally and theoretically, with special attention to the critical scaling exponents associated with the phase transitions, i... The ferroelectric transitions of several SrTiO3-based ferroelectrics are investigated experimentally and theoretically, with special attention to the critical scaling exponents associated with the phase transitions, in order to understand the competition among quantum fluctuations (QFs), quenched disorder, and ferroelectric ordering. Two representative systems with sufficiently strong QFs and quenched disorders in competition with the ferroelectric ordering are investigated. We start from non-stoichiometric SrTiO3(STO) with the Sr/Ti ratio deviating slightly from one, which is believed to maintain strong QFs. Then, we address Ba/Ca co-doped Sr1-x(Ca0.6389Ba0.3611)xTiO3(SCBT) with the averaged Sr-site ionic radius identical to the Sr2+ ionic radius, which is believed to offer remarkable quenched disorder associated with the Sr-site ionic mismatch. The critical exponents associated with polarization P and dielectric susceptibility ε, respectively, as functions of temperature T close to the critical point Tc, are evaluated. It is revealed that both non-stoichiometric SrTiO3 and SCBT exhibit much bigger critical exponents than the Landau mean-field theory predictions. These critical exponents then decrease gradually with increasing doping level or deviation of Sr/Ti ratio from one. A transverse Ising model applicable to the Sr-site doped STO (e.g., Sr1-xCaxTiO3) at low level is used to explain the observed experimental data. It is suggested that the serious deviation of these critical exponents from the Landau theory predictions in these STO-based systems is ascribed to the significant QFs and quenched disorder by partially suppressing the long-range spatial correlation of electric dipoles around the transitions. The present work thus sheds light on our understanding of the critical behaviors of ferroelectric transitions in STO in the presence of quantum fluctuations and quenched disorder, whose effects have been demonstrated to be remarkable. 展开更多
关键词 critical exponents quantum fluctuations ferroelectric phase transitions
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ASYMPTOTICS FOR A CLASS OF p-LAPLACE EQUATION INVOLVING CRITICAL GROWTH ON BALL
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作者 耿堤 薛亚芬 《Annals of Differential Equations》 2002年第1期14-26,共13页
In this paper a general weighted p-Laplacian equation involving critical growth and singular coefficients is considered on the unit ball, rather complete results are obtained for asymptotic behavio... In this paper a general weighted p-Laplacian equation involving critical growth and singular coefficients is considered on the unit ball, rather complete results are obtained for asymptotic behavior of positive solutions as λ→0+. This problem includes p- Laplacian, weighted Laplacian, and the Hessian operators which are special cases of our result. 展开更多
关键词 p-Laplace operator asymptotic behavior critical exponents
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Criticality of QCD in a holographic QCD model with critical end point
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作者 Xun Chen Danning Li Mei Huang 《Chinese Physics C》 SCIE CAS CSCD 2019年第2期46-52,共7页
The thermodynamics of strongly interacting matter near the critical end point are investigated in a holographic QCD model, which can describe the QCD phase diagram in T-μ plane qualitatively. Critical exponents along... The thermodynamics of strongly interacting matter near the critical end point are investigated in a holographic QCD model, which can describe the QCD phase diagram in T-μ plane qualitatively. Critical exponents along different axes(α,β,γ,δ) are extracted numerically. It is given that α≈0,β≈0.54,γ≈1.04, and δ≈2.97,which is similar to the three-dimensional Ising mean-field approximation and previous holographic QCD model calculations. We also discuss the possibilities to go beyond the mean field approximation by including the full back-reaction of the chiral dynamics in the holographic framework. 展开更多
关键词 critical exponents HOLOGRAPHIC QCD THERMODYNAMICS
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Critical Exponents of Quark Matter
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作者 Hosein Gholizade 《Journal of Modern Physics》 2013年第2期280-284,共5页
I investigate the ferromagnetic phase transition inside strong quark matter (SQM) with one gluon exchange interaction between strong quarks. I use a variational method and the Landau-Fermi liquid theory and obtain the... I investigate the ferromagnetic phase transition inside strong quark matter (SQM) with one gluon exchange interaction between strong quarks. I use a variational method and the Landau-Fermi liquid theory and obtain the thermodynamics quantities of SQM. In the low temperature limit, the equation of state (EOS) and critical exponents for the second-order phase transition (ferromagnetic phase transition) in SQM are analytically calculated. The results are in agreement with the Ginzberg-Landau theory. 展开更多
关键词 QUARK MATTER critical exponents EXCHANGE INTERACTION
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