几乎次亚可膨胀空间的逆极限性质

该文主要证明如下结果:设X=lim←{χα,παβ},λ=｜∧｜并且每个投射πα是开满映射.如果X是λ-仿紧的且每个Xα是几乎次亚可膨胀的,则X是几乎次亚可膨胀的.     

cf-可膨胀类的逆极限运算的保持性

主要证明如下结果：设X=lim←{Xα,πβα,Λ},λ=｜Λ｜并且每个投射πα是开满映射,如果X是（遗传）λ-仿紧的且每个Xα是性质P（遗传性质P）的,则X是性质P（遗传性质P）的.P表示cf-可膨胀、θ-cf可膨胀、序列cf-可膨胀、离散cf-可膨胀、离散θ-cf可膨胀,离散序列cf-可膨胀6种性质之一.     

σ-cf-可膨胀空间的逆极限性质

设X=lim｛Xα,παβ,Λ｝,λ=|Λ|,如果X是λ 仿紧的且每个Xα是σ cf 可膨胀的(σ csf 可膨胀的),则X是σ cf 可膨胀的(σ csf 可膨胀的)。     

正规弱次亚紧空间Tychonoff乘积的刻画

文章主要证明了如下结果:(1)如果X=∏α∈ΛXα是|Λ|仿紧空间,则X是正规弱次亚紧的当且仅当(∨)F∈[Λ]＜ω,∏α∈FXα是正规弱次亚紧的;(2) 如果X=∏i∈ωXi是可数仿紧的,则下列三条等价: X是正规弱次亚紧的;(∨)F∈[ω]＜ω,∏i∈FXi是正规弱次亚紧的;(∨)n∈ω,∏i≤nXi 是正规弱次亚紧的.     

亚紧空间和σ-亚紧空间的无限乘积

主要证明了如下结果 :用P表示下列诸覆盖性质之一 :亚紧 ;次亚紧 ;弱次亚紧 ;σ -亚紧 .( 1)如果X =∏α∈ΛXα 是 |Λ| -仿紧空间 ,则X具有P当且仅当 F∈ [Λ]<ω,∏α∈FXα 具有P ;( 2 )如果X =∏i∈ωXi 是可数仿紧的 ,则下列三条等价 :X具有P : F∈ [ω]<ω,∏i∈FXi具有P : n <ω ,∏i≤nXi,具有P .     

关于B_2-可膨胀空间

对B2-可膨胀空间进行研究,得到主要结论如下:(1)若X=lim←{Xα,πβα,∑}并且每个πα是开满映射,如果X是|∑|-完满正规的,并且每个Xα都是B2-可膨胀的,则X是B2-可膨胀的;(2)若X=lim←{Xα,παβ,∑}并且每个πα是开满映射,如果X是遗传|∑|-完满正规的,并且每个Xα都是遗传B2-可膨胀的,则X是遗传B2-可膨胀的。     

几乎基次亚紧空间的无限乘积

为了更好地研究次亚紧空间及其他拓扑空间的覆盖性质,在与几乎基亚紧空间结合后定义了几乎基次亚紧空间,研究了它的遗传性,并获得结果:(1)几乎基次亚紧空间的闭子空间是几乎基次亚紧的;(2)如果X=∏α∈ΛXα是︱Λ︱-仿紧空间,则X是几乎基次亚紧空间当且仅当F∈[Λ]<ω,︱Λ︱是几乎基次亚紧的。     

遗传正规弱■-可加空间的无限Tychonoff乘积性质

证明(1)如果X=∏α∈ΛXα是遗传|Λ|-仿紧空间,则X是遗传正规弱■-可加的当且仅当F∈[Λ]<ω,∏α∈FXα是遗传正规弱■-可加的;(2)如果X=∏i∈ωXi是遗传可数仿紧的,则下列条件等价:(i)X是遗传正规弱■-可加的,(ii)F∈[Λ]<ω是遗传正规弱■-可加的,(iii)n∈ω,∏i≤nXi,α∈∏FXα是遗传正规弱■-可加的.     

次中紧空间与遗传次中紧空间

证明了X是次中紧空间当且仅当X的每个散射分解有一个θ-cf-开膨胀;空间X的每个散射分解有一个θ-cf-开膨胀,则X是遗传次中紧的,反之不一定成立且给出一个反例。最后给出了次中紧空间的一个相关结论。     

集体次正规空间的逆极限与无限 Tychonoff积

主要证明:(1)并且每个是开满映射,如果X是|∑|-完满的且每个Xσ是集体次正规空间,则X是集体次正规空间．(2)如果是|A|-完满正规的,则X是集体次正规空间当且仅当是集体次正规的．同时指出:遗传集体次正规也有相应的性质．     

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.     

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     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

正~~     

Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has