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奇数阶中立型微分方程微正解或微负解判据 被引量:1
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作者 计国君 宋文忠 《东南大学学报(自然科学版)》 EI CAS CSCD 1995年第6期19-24,共6页
本文给出了奇数阶中立型微分方程在不同的变系数情形下微正解或微负解存在的判据。
关键词 中立型 分方程 振动 微正解
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中立型微分方程的强迫振动性
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作者 计国君 王政贤 赖定文 《东南大学学报(自然科学版)》 EI CAS CSCD 1995年第1期88-93,共6页
本文给出了中立型微分方程的强迫振动准则,且根据方程的不同特点得到了不同的振动性条件。
关键词 振动 中立型 分方程 最终 微正解
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The Solvability of the Degenerate Differential Systems with Delay 被引量:5
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作者 蒋威 郑祖庥 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期1-7,共7页
In this paper we study the degenerate differential system with delay:E(t)=Ax(t)+Bx(t-1)+f(t),give the canonical form of this systems and study this form of degeneration system with delay,have some results for the so... In this paper we study the degenerate differential system with delay:E(t)=Ax(t)+Bx(t-1)+f(t),give the canonical form of this systems and study this form of degeneration system with delay,have some results for the solvability of such systems and the uniqueness of their solutions. 展开更多
关键词 degenerate differential system with delay regular system SOLVABILITY
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Influence of carbon coating prepared by microwave pyrolysis on properties of LiNi_(1/3) Mn_(1/3) Co_(1/3) O_2
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作者 韩亚梅 张正富 +4 位作者 张利波 彭金辉 傅梦笔 C.SRINIVASAKANNAN 杜江 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期2971-2976,共6页
A novel synthesis method of carbon-coated LiNil/3Mnl/3COl/302 cathode material for lithium-ion battery was reported. The carbon coating was produced from a precursor, glucose, by microwave-pyrolysis method. The prepar... A novel synthesis method of carbon-coated LiNil/3Mnl/3COl/302 cathode material for lithium-ion battery was reported. The carbon coating was produced from a precursor, glucose, by microwave-pyrolysis method. The prepared powders were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) and charge/discharge tests. XRD results indicate that the carbon coating does not change the phase structure of LiNil/3Mnl/3C01/302 material. SEM results show that the surface of spherical carbon-coated material becomes rough. Electrochemical performance results show that the carbon coating can improve the cycling performance of LiNii/3Mnl/3C01/302. The specific discharge capacity retention of the carbon-coated LiNi1/3Mnt/3Col/30z reached 85.0%-96.0% at the 50th cycle at 0.2C rate, and the specific discharge capacity retention is improved at a high rate. 展开更多
关键词 lithium-ion battery cathode material carbon coating microwave pyrolysis method electrochemical performance
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On Miranda's Normal Criterion
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作者 仇惠玲 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期274-276,共3页
In this paper, we study the normality of a family of analytic functions and prove the following theorem. Let F be a family of analytic functions in a domain D , k be a positive integer and a(z) , a 1(z) , a 2(z) , ...... In this paper, we study the normality of a family of analytic functions and prove the following theorem. Let F be a family of analytic functions in a domain D , k be a positive integer and a(z) , a 1(z) , a 2(z) , ... , a k(z) be analytic in D such that a(z)0 . If f(z)≠0 and the zeros of f (k) (z)+a 1(z)f (k-1) (z)+...+a k(z)f(z)-a(z) are of multiplicity at least 2 for each f∈F , then F is normal in D . This result improves Miranda s norm... 展开更多
关键词 entire function analytic function NORMALITY differential polynomial
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Oscillation of Unstable Second Order Neutral Differential Equations with Positive and Negative Coefficients
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作者 徐继军 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期72-75,共4页
This paper discusses a class of unstable second order neutral differential equations with positive and negative coeffcients. Sufficient conditions for all bounded solutions of the equations to be oscillatory are obtai... This paper discusses a class of unstable second order neutral differential equations with positive and negative coeffcients. Sufficient conditions for all bounded solutions of the equations to be oscillatory are obtained. 展开更多
关键词 neutral equation UNSTABLE OSCILLATION
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On the Existence of Positive Solutions for Impulsive Neutral Differential Equations
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作者 何智敏 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期352-356,共5页
Aim To investigate the existence of positive solutions for impulsive neutral differential equations. Methods The Banach contraction principle was used to establish our results. Results and Conclusion The results of... Aim To investigate the existence of positive solutions for impulsive neutral differential equations. Methods The Banach contraction principle was used to establish our results. Results and Conclusion The results of the existence of positive solutions for impulsive neutral differential equations are obtained. 展开更多
关键词 impulsive neutral differential equation positive solution Banach contraction principle
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Positive Solutions of p-Laplacian Functional Difference Equations 被引量:1
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作者 SONG Chang-xiu 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第4期475-481,共7页
In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the p... In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the positive solutions. 展开更多
关键词 p-Laplacian operator functional difference equations positive solution CONE
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On the Existence of Positive Solutions of Neutral Differential Equations
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作者 李青阳 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期77-80,共4页
Consider the first order neutral delay differential equation with positive and negative coefficients:[x(t)-c(t)x(t-γ)]+p(t)x(t-τ)-Q(t)x(t-δ)=0,t≥t 0,(1)where c,p,Q∈C((t 0,∞),R +),R +=(0,∞),γ】0,t】δ≥0. W... Consider the first order neutral delay differential equation with positive and negative coefficients:[x(t)-c(t)x(t-γ)]+p(t)x(t-τ)-Q(t)x(t-δ)=0,t≥t 0,(1)where c,p,Q∈C((t 0,∞),R +),R +=(0,∞),γ】0,t】δ≥0. We obtain the sufficient condition for the existence of positive solutions of Eq.(1). As a corollary, we improve the correspondent result in by removing the condition∫ ∞ c 0 (t) d t=∞,where (t)=p(t)-Q(t-τ+δ)≥0. 展开更多
关键词 positive solution neutral different equation OSCILLATION
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Existence of positive solutions in a delay logistic difference equation
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作者 周英告 《Journal of Central South University of Technology》 EI 2002年第2期142-144,共3页
The author studied the existence of positive solutions of the delay logistic difference equation Δ y n=p ny n(1-y τ(n) ), n =0,1,2,.... where { p n } is a sequence of positive real numbers, { τ(n) } is a nondecreas... The author studied the existence of positive solutions of the delay logistic difference equation Δ y n=p ny n(1-y τ(n) ), n =0,1,2,.... where { p n } is a sequence of positive real numbers, { τ(n) } is a nondecreasing sequence of integers, τ(n)<n and lim n →∞ τ(n) =∞. A sufficient condition for the existence of positive solutions of the equation was given. 展开更多
关键词 positive solutions logistic delay difference equation OSCILLATION
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Solitary Wave and Periodic Wave Solutions for the Relativistic Toda Lattices 被引量:2
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作者 MAZheng-Yi ZHUJia-Min ZHENGChun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期27-30,共4页
In this work, an adaptation of the tanh/tan-method that is discussed usually in the nonlinear partial differential equations is presented to solve nonlinear polynomial differential-difference equations. As a concrete ... In this work, an adaptation of the tanh/tan-method that is discussed usually in the nonlinear partial differential equations is presented to solve nonlinear polynomial differential-difference equations. As a concrete example,several solitary wave and periodic wave solutions for the chain which is related to the relativistic Toda lattice are derived.Some systems of the differential-difference equations that can be solved using our approach are listed and a discussion is given in conclusion. 展开更多
关键词 tanh-method solitary wave and periodic wave solutions differential-difference equation Toda lattice
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The Uniqueness and Nonexistent Results for Some Nonlinear Partial Equations on Riemannian Manifolds
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作者 李兴校 曹林芬 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期344-351,共8页
The paper studies a class of nonlinear elliptic partial differential equations on a compact Riemannian manifold (M,g) with some curvature restriction. The authors try to prove some uniqueness and nonexistent results... The paper studies a class of nonlinear elliptic partial differential equations on a compact Riemannian manifold (M,g) with some curvature restriction. The authors try to prove some uniqueness and nonexistent results for the positive solutions of the equations concerned. 展开更多
关键词 compact Riemannian manifold nonlinear elliptic equation positive solution uniqueness and nonexistance
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Isolation and in-situ bioremediation of halophile oil degradation bacteria
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作者 LIU Xian-bin LIANG Meng-yu LIU Xing-wei 《Marine Science Bulletin》 CAS 2016年第2期1-14,共14页
Crude oil exploration has resulted in alarming pollution. It is thereforenecessary to isolate native bacterial strains for contaminated crude oil bioremediation.In this study, three bacteria strains were isolated from... Crude oil exploration has resulted in alarming pollution. It is thereforenecessary to isolate native bacterial strains for contaminated crude oil bioremediation.In this study, three bacteria strains were isolated from the Dagang Oil Field, Tianjing,China, which belonged to the genera Pseudomonas sp. and Bacillus sp., as determinedby 16S rRNA genera sequence similarity analysis. The optimum degradation conditionsof the three bacteria were studied by single factor experiment, and they were 30 °C, 7.2pH, and 3% salinity, 35 °C, 7.5 pH, and 3% salinity, and 37 °C, 7.5 pH, and 5% salinity,respectively. The results showed that the oil degradation rate was the best when theproportion of the different strains was 2:1:2. Moreover, the most effective treatmentconditions were found by orthogonal test to be 10% inoculum, 0.2% oil content, 7.0 pH,3:1 N:P, 3.5% salinity, and 35 °C, the oil degradation rate reached 71.03% under thiscondition. 展开更多
关键词 microbial degradation REMEDIATION orthogonal test HALOPHILE
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B→ρ(ω,φ)η(′)Decays and NLO Contributions in pQCD Approach 被引量:1
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作者 ZHANG Zhi-Qing XIAO Zhen-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期885-894,共10页
By employing the perturbative QCD (pQCD) factorization approach, we calculate some important next- to-leading-order (NLO) contributions to the two-body charmless hadronic decays B^+ →ρ^+η(') and B^0 → ρ^... By employing the perturbative QCD (pQCD) factorization approach, we calculate some important next- to-leading-order (NLO) contributions to the two-body charmless hadronic decays B^+ →ρ^+η(') and B^0 → ρ^0(ω, φ)η('), induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that (a) for B^± → ρ^±η(') (B^0 → ρ^0(ω, φ)η(')decays, the partial NLO contributions to branching ratios are small (large) in magnitude; and (b) the pQCD predictions for ACP^dir(B^± → ρ^±η(')) are consistent with the data, while the predicted .ACP(B^0 → ρ^0(ω)η(')) are generally large in magnitude and could be tested by the forthcoming LHCb experiments. 展开更多
关键词 pQCD factorization approach B meson decays branching ratio CP-violating asymmetry
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Boundary Value Problems of Quasi-linear Ordinary Differential Equations on the Semi-infinite Interval
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作者 YANG Hui-sheng MA Yun-xin 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第3期331-337,共7页
Existence of positive solution is established for boundary value problems of nonsingular for a class quasi-linear ordinary differential equation on the semi-infinite interval. The results are obtained by using the non... Existence of positive solution is established for boundary value problems of nonsingular for a class quasi-linear ordinary differential equation on the semi-infinite interval. The results are obtained by using the nonlinear alternative of Leray-Schauder method. 展开更多
关键词 positive solution quasi-linear ordinary differential equation EXISTENCE
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A Predictor-Corrector Scheme for the Microscopic Depletion Solver of the COCAGNE Core Code
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作者 Fabrice Hoareau Nadine Schwartz David Couyras 《Journal of Energy and Power Engineering》 2012年第3期369-378,共10页
EDF R&D is developing a new calculation scheme based on the transport-Simplified Pn (SPn) approach. The lattice code used is the deterministic code APOLLO2, developed at CEA. The core code is the code COCAGNE, deve... EDF R&D is developing a new calculation scheme based on the transport-Simplified Pn (SPn) approach. The lattice code used is the deterministic code APOLLO2, developed at CEA. The core code is the code COCAGNE, developed at EDF R&D. The latter can take advantage of a microscopic depletion solver expected to improve the treatment of spectral history effects. However, the direct use of the microscopic depletion solver is computationally very intensive because very small evolution steps (typically 100 MWd/t) are needed to reach a good accuracy, which is not always compatible with industrial applications. In order to reduce the calculation time associated with the use of the microscopic depletion solver, a predictor-corrector scheme has been implemented within COCAGNE. It enables the use of larger evolution steps, up to 1000 MWd/t. Tests show that the predictor-corrector procedure gives fairly accurate results while significantly reducing the calculation time. 展开更多
关键词 Neutronic simulation microscopic depletion predictor-corrector.
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The Smoothness of Weak Solutions to the System of Second Order Differential Equations with Non-negative Characteristics
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作者 张克农 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第4期15-22,共8页
In this paper,we will discuss smoothness of weak solutions for the system of second order differential equations eith non-negative characteristies.First of all,we establish boundary,and interior estimates and then we ... In this paper,we will discuss smoothness of weak solutions for the system of second order differential equations eith non-negative characteristies.First of all,we establish boundary,and interior estimates and then we prove that solutions of regularization problem satisfy Lipschitz condition. 展开更多
关键词 diff equa with non-negative characteristics regularization weak solution boundary and interior estimate
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Globally Asymptotic Stability of Equilibrium of a Dynamical Model with Infinite Delay
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作者 LIXiang WENGPei-xuan 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期121-128,共8页
By using a criterion for asymptotic stability in Banach space BC, a group of sufficient condi-tioas for a dynamical model with infinite delay which is derived from hematology were obtained, which refined the result in... By using a criterion for asymptotic stability in Banach space BC, a group of sufficient condi-tioas for a dynamical model with infinite delay which is derived from hematology were obtained, which refined the result in the reference [ 10] got by the second author herself. 展开更多
关键词 integro-differential equation infinite delay EQUILIBRIUM globally asymptotic stability
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Existence of Positive Solutions to Second Order Neumann Boundary Value Problems 被引量:31
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作者 蒋达清 刘辉昭 《Journal of Mathematical Research and Exposition》 CSCD 2000年第3期360-364,共5页
The existence of positive solutions to second-order Neumann BVPs -u' + Mu = f(t, u), u'(0) = u'(1) = 0 and u' + Mu = f(t, u), u'(0) =u'(1) is proved by a simple application of a Fixed Poin... The existence of positive solutions to second-order Neumann BVPs -u' + Mu = f(t, u), u'(0) = u'(1) = 0 and u' + Mu = f(t, u), u'(0) =u'(1) is proved by a simple application of a Fixed Point Theorem in cones due to Krasnoselskii[1,6]. 展开更多
关键词 Neumann BVP positive solutions the fixed point theorem.
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Existence of Solutions to a Class of Higher-Order Singular Boundary Value Problem for One-Dimensional p-Laplacian
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作者 田玉 葛渭高 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2007年第2期282-288,共7页
This paper deals with the existence of positive solutions for the problem {(Фp(x^(n-1)(t)))′+f(t,x,…,x^(n-1)=0,0〈t〈1, x^(i)(0)=0,0≤i≤n-3, x^(n-2)(0)-B0(x^(n-1)(0))=0,x^(n-2)(1)+B1... This paper deals with the existence of positive solutions for the problem {(Фp(x^(n-1)(t)))′+f(t,x,…,x^(n-1)=0,0〈t〈1, x^(i)(0)=0,0≤i≤n-3, x^(n-2)(0)-B0(x^(n-1)(0))=0,x^(n-2)(1)+B1(x^(x-1)(1))=0, where Фp(s) = |s|^p-2s, p 〉 1. f may be singular at x^(i) = 0, i = 0,...,n- 2. The proof is based on the Leray-Schauder degree and Vitali's convergence theorem. 展开更多
关键词 singular higher-order differential equation positive solution Vitali's convergence theorem.
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