流体媒质三次谐波及三阶非线性声参量研究

从流体动力学的基本方程出发,采用逐级近似微扰法,建立了理想流体媒质－至三级近似的波动方程,并得到三次谐波声压的积累解与声波传播距离的平方成正比,在此基础上进而求得三阶非线性声参量C／A与三次谐波声压之间的关系,这为下一步用有限振幅法测量和研究流体媒质的三阶非线性声参量C／A提供了理论依据,而三阶非线性参量预期在医学超声参数成像技术中有重要的应用前景。     

光纤非线性光学显微成像

在光学显微成像领域，基于光纤的小型非线性光学显微镜和内窥镜作为传统显微镜和其他光学成像方法的一种重要补充形式，近几年来受到人们的关注．该文介绍和总结了光纤非线性光学显微成像技术及其在生物医学中的应用．首先介绍了结合非线性光学显微技术和单模光纤耦合器获得小型非线性光学显微镜的方法；特别对基于双包层光子晶体光纤和微电机系统扫描镜的光纤非线性内窥成像系统进行了分析；最后通过消化器官的组织成像实验说明了光纤非线性光学显微镜的重要应用．研究证明了基于光纤和微电机系统MEMS扫描镜的非线性内窥镜的新概念，并用于生物组织的成像．     

下丘脑-垂体-睾丸轴激素的振荡行为与非线性动力学模型

提出了一个新的下丘脑垂体一睾丸轴激素分泌的非线性动力学模型.该模型修改了以往模型中的动力学特征参量,考虑了催乳素(prolactin,PRL)等激素对性腺系统的影响以及与体内相关激素的相互作用,得到了系统内各激素浓度的振荡解与实验相符,能较好地说明该系统中性腺激素睾酮的脉冲分泌现象.     

潜艇垂直面运动的非线性滑动控制

对潜艇运动模型进行了合理简化，考虑了水平面与垂直面运动参量的耦合影响，通过运动方程估计垂向速度，对ＭＩＭＯ非线性系统直接进行联合操舵滑动控制规律的设计，研究了潜艇航深稳定和潜浮运动两种控制问题，得出的控制算法简单，易于实现。仿真结果表明，控制效果良好。     

铌酸锂波长转换器中参量过程的研究

考虑到抽运损耗、走离和非线性等效应,对周期性极化LiNbO3光波导的级联二阶非线性效应波长转换中的参量过程进行了理论研究及数值分析,结果表明:抽运光、信号光和差频光之间会发生周期性能量振荡,最优波导长度随抽运光和信号光的注入功率的增大而减小;脉冲抽运时因走离效应的影响,能量振荡相对较弱.利用这种能量振荡特性,通过调整注入控制光功率大小在实现信号波长转换的同时可以实现脉冲整形.     

液体非线性声参量与分子结构的关系研究

为了寻求简单液体的非线性声参量与分子微观量的关系，基于Flory液体理论，推导出有机液体的非线性声参量与表征分子结构参量的关系式，并通过理论值与试验值的比较，验证了该关系的可靠性．结果表明，液体的非线性声参量决定于分子的结构，从而表达了分子级的信息．     

基于准参量非线性晶体的非厄米超快激光放大

激光振荡器锁模是激光物理中的重要发现和超快科学中的核心技术，其本质是以耗散调控增益，进而改变激光振荡行为.这种以耗散调控增益的概念离不开谐振腔的反馈耦合，长期以来多局限于激光振荡器.对此，本文首先提出了准参量非线性的概念，不同于传统的二阶非线性光参量过程，准参量非线性基于耗散闲频光的准参量晶体，通过非线性耦合实现了以闲频光耗散对信号光放大的调控，对应着量子理论中的具有宇称-时间对称性的非厄米体系.准参量的放大行为由信号光增益、闲频光耗散以及非线性耦合三者之间的相互作用决定，起始阶段的信号光放大继续保持传统光参量放大的特性，而在最终的饱和放大阶段则呈现出类似能级型放大的非参量特性，从而同时具备光参量放大和激光能级型放大的综合优势.其次给出了准参量非线性的反直觉的超快应用：实现无需谐振腔的放大器锁模.最后，对这种基于准参量晶体的非厄米超快激光放大在激光物理创新中的更多未来应用前景进行总结展望.     

多元有机混合液体非线性声参量的混合定则

给出了多元有机混合液体的非线性声参量所满足的混合定制，在组成混合液体非线性声参量、摩尔分数、内表面积、自由程参量已知的情况下，可以计算出混合液体的非线性声参量。实验测量结果与混合定则给出的理论值符合较好。     

光电成像系统非线性效应建模

系统分析了光电成像系统的非线性效应所涉及的几何扭曲、渐晕、采样效应、噪声特性、非线性响应特性、图像重构算法,并对其进行了建模,对于光电成像仿真、系统性能评价具有重要意义。     

非线性电路故障诊断模型的建立及神经网络求解的方法研究

分析并推导了含有非线性流控型电阻元件和非线性压控型电阻元件组成的非线性电阻网络的故障诊断方程，这是以支路故障标志量为未知的一组线性代数方程。在推导非线性元件的“故障标志量”时，消除由工作点变化引起的电参量的变化，保留由伏-安特性变化引起的电参量变化，它标志非线性元件本身发生了故障；文章还提出一种神经网络，可在线快速求解非线性电阻网络的故障方程的解，从而可在线对故障进行定位。     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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