椭园型方程广义解的Hlder连续性

本文对文[1]作如下推广:文[1]关于α(x)和,f(x)是在α(x),f(x)∈L_p(G),p=n/(1-λ)条件下([1]中误为p=n/(2-λ))得到一系列结果,本文在α(x),f(x)∈L_p(G),     

Ore条件弱化下的Hamilton性

让G(V,E)是n阶图,在Ore条件下,即G的不相邻的任意两点x,y均有d(x)+d(y)≥n,则G是Hamilton图.进一步考虑G的不相邻的任意两点x,y均有d(x)+d(y)≥n-1,和长为2的任意两点x,y均有d(x)+d(y)≥n-1,两个条件下G的Hamilton性.     

方程+f(X,)+g(X)=0的极限环

书[1]对84年以前国内外有关极限环理论的重要成果作了总结和介绍,文[2]和文[3]是纳入[1]的两个定理,分别给出了方程+f(x,)+g(x)=0和方程+F()+G(x)=0存在稳定极限环的充分条件。本文给出更加广泛的二阶非线性方程+f(x,)+g(x)=0存在稳定极限环的一组充分条件。文[2]对f(x,)所加条件主要是针对x给出,本文则主要针对给出,且估值方法有所不同。而文[3]可认为是本文定理的特例或推论,文[3]的方法较繁。     

哈密尔顿图与泛圈图的几个性质的探讨

让NC＝min｛U（x)∪N(y)||x,y∈V(G),xy不属于E（G|｝,R.J.Faudree等曾得到NC≥n-δ,则G是哈密尔顿图。本文进一步研究NC≥n-δ-1的哈密顿性，推广了文前人的结果。     

本原勾股数组数G(x)的渐近阶猜想的证明

丢番图方程 a2 b2 =c2 满足条件 a >0 ,b>0 ,c>0 ,(a,b) =1的整数解 (a,b,c)称为本原勾股数 .设 x为给定的正实数 ,用 G(x)表示弦 c≤ x的所有本原勾股数 (a,b,c)的组数 .在此证明了文 [1 ]提出的本原勾股数组数 G(x)的渐近阶猜想 G(x) =1πx O(x12 logx)的正确性 ,由此推得 limx→ ∞G(x)x =1π,即弦 c≤ x的所有本原勾股数 (a,b,c)的组数的平均阶为 1π.     

关于一类非自治非线性系统零解的稳定性的注记

在文[2]的基础上,我们考虑非自治非线性系统: (dx/dt)=G(t,x)F(x)(·)这里G(t,x)为n×n矩阵,F(x)为n维向量。运用向量ляпунов函数得到(·)的稳定性判据。改进了文[1],[2]的部分结果。     

一类特殊的有限p-群

探讨了一类特殊的有限p -群,即对任意x,y∈G,如果[x,y]≠1,那么《x,y》(△)-G.主要证明了:如果满足这样条件的有限p -群G＝《x1,x2,…,xn》,其中对任意x∈G,《x》G是交换群或者内交换群.     

捕食—被捕食系统解的有界性定理的研究

美国Fred Brauer教授于1979年在文[1]中建立了一般捕食-被捕食系统(1)的一个有界性定理,其中x,y分别表示食饵与捕食种群的数量.f(x,y),g(x,y),分别表示两种群的增长率.F,G是常数,当F>0,G>O时,分别表示食饵与捕食者的收获率.当F<0,G<0时,分别表示食饵与捕食者的投放率.F和G可以一个等于零,也可以同时为零.经过分析研究发现文[1]中的有界性定理,在β(F)≠∞时,结论是正确的,但证明不够完善.在β(F)=∞时,证明有漏洞,其结果有错误.并且举出了反例. 文[1]假设捕食一被捕食系统(1)满足下面条件     

关于模糊关系与模糊子群的注记

首先讨论了σα成为模糊子群的条件,并证明了如下两个主要结果:(1)设群G上的模糊关系μ是群G×G的一个模糊子群,α∈G,则σα是G的模糊子群当且仅当σα(x)≤σα(e),x∈G;(2)设群G上的模糊关系μ是群G×G的一个模糊子群,α∈G.如果σα是G的一个模糊子群,则对 x∈G有σα(x)=σα(e)或σα(x)=σα(x).通过一个反例指出了文献[1]中的三个结论是错误的.     

不变集的区域稳定性

本文继续文[1]的工作,将研究对象推广到(不变)集合中去,讨论不变集的区域稳定性. 考虑n维欧几里得空间中的区域D及微分方程组 =f(t,x) (1)这里D可以是部分无界、部分有界而其边界也可以是部分开、部分闭的复杂区域,x、f为n维向量,f(t,x)在域G={(x,t):t≥0,x∈D}中定义且满足方程(1)解的存在唯一性条件.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the