绝热放电现象和粒子碰撞对磁化尘埃等离子体中、低频静电波稳定性的影响

考虑到尘埃绝热放电现象、外磁场、碰撞、离子与尘埃温度之比、电子与离子数密度之比以及斜传播等因素对均匀尘埃等离子体中低频静电波的影响，其中包括高能离子和玻耳兹曼分布电子，运用简正模分析法，得出了低频波的色散关系．研究表明，以上诸因素对低频波有很大影响．研究中包括两种不同的低频波模式．在研究斜传播对低频波的影响时，发现当θ=π／2时，第一种模式是稳定的；而第二种模式存在一个稳定区域，即1.3≤θ≤1.7.     

绝热放电现象和粒子碰撞对磁化尘埃等离子体中低频静电波稳定性的影响

考虑到尘埃绝热放电现象、外磁场、碰撞、离子与尘埃温度之比、电子与离子数密度之比以及斜传播等因素对均匀尘埃等离子体中低频静电波的影响,其中包括高能离子和玻耳兹曼分布电子,运用简正模分析法,得出了低频波的色散关系.研究表明,以上诸因素对低频波有很大影响.研究中包括两种不同的低频波模式.在研究斜传播对低频波的影响时,发现当θ=π/2时,第一种模式是稳定的;而第二种模式存在一个稳定区域,即1.3≤θ≤1.7.     

磁化等离子体中的离子声波

研究了存在外磁场时等离子体中的低频离子声孤波,得到了描述等离子体中有限小振幅的离子声波的ZK方程,同时给出了离子声波电势的孤波解。研究结果发现,对于波只沿一维传播的情况,外磁场对波的特性没有影响。     

部分电离等离子体中离子声波的阻尼

基于部分电离等离子体的三流体方程,得到了离子声波的色散关系,画出了其色散曲线.结果表明:由于碰撞、电离与复合的影响,离子声波的相速度小于完全电离的情况,当波的频率接近离子有效碰撞频率时其阻尼率最大.     

非线性尘埃声波在含有2种不同温度离子的尘埃等离子体中的稳定性问题

在无磁场的尘埃等离子体中 ,由冷的尘埃颗粒和热的电子和离子组成的尘埃等离子体 ,对于有限的小振幅的非线性波的运动可以用KdV方程描述 .对由 2种不同温度离子的尘埃等离子体中的弱二维尘埃声波 ,得到了它所满足的KP方程 .并且发现 ,在横向扰动下 ,弱的非线性孤立波在尘埃等离子体中是稳定的 .在这个系统中既存在压缩孤立波又存在稀疏孤立波     

非线性尘埃-漂移波的复杂结构

采用流体模型，研究尘运行等离子体中的非线性尘埃－漂移波。极低频的尘埃－静电漂移波，通过非线性互相作用，形成局域的涡旋结构。研究发现，涡旋强度与等离子体中尘埃含量和离子－电子温度比有密切的关系。等离子体中形成的大量涡旋横越磁场运动，导致了等离子体的反常输运。     

等离子体中(3+1)维弱非线性离子声波的摄动分析

通过约化摄动法,获得了等离子体中离子声波的(3 1)维KP(Kadomtsev Petviashvili)方程.结果表明,离子声波沿轴方向的速度分量、密度和电位势,在垂直方向有色散的情况下,仍然有孤立波解出现,但其它2个垂直方向的速度分量不会出现孤波结构.     

离子回旋频段内热等离子体介电张量研究

给出了离子回旋频段内冷等离子体和热等离子体介电张量表达式,计算得到了其分布,并进行了对比.结果表明:热等离子体更能反映托卡马克等离子体的介电性质,在托卡马克离子回旋波电流驱动的相关研究中应尽量采用热等离子体模型.     

电子的非广延分布对复杂多组分热等离子体中(1+1)维非线性离子声孤波的影响

通过约化摄动方法,研究了电子的非广延分布对多组分热等离子体中(1+1)维非线性离子声孤波.推导得到了用来描述非线性离子声波运动过程的KdV方程,并利用数值模拟的方法,发现复杂等离子体系统的各种参数对非线性离子声孤波的振幅、宽度和波形等存在重要影响.     

基于格子Boltzmann方法的量子等离子体离子声波的数值模拟

用格子Boltzmann方法(LBM)研究由KPB(Kadomtsev-Petviashvili-Burgers)方程控制的量子等离子体中离子声波的数值模拟问题, 得到了KPB方程中离子声波的传播演化结果.     

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     

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     

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

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