光折变晶体双光束耦合调制度变化特性的研究

测量了Ce:KNSBN晶体双光束耦合调制度随入射光强比的变化特性,用中间段光折变理论对变化关系进行了参数理论分析,理论结果和实验结果定性符合。     

光擦除双光束耦合理论和实验研究

章基于光擦除折射率光栅和光束耦合提出了一相新的光折变非线性光学模型。用带导模型和耦合波方程了理论公式。用Ｃｅ：ＫＮＳＢＮ单晶和Ｈｅ－Ｎｅ激光进行了实验验证。结果表明,理论分析和实验结果定性地吻合。     

温度对KNSBN晶体二波耦合增益的影响

对３００Ｋ至４２０Ｋ温度范围内的光折变晶体ＫＮＳＢＮ（钾钠铌酸锶钡）的前向二波耦合特性进行了实验观测和理论分析，结果表明，光增益不仅取决于实验的几何配置而且对温度有较大的依赖性，由室温度提高至３６０Ｋ可提高放大倍数一倍以上。     

光折变位相共轭镜表面反射不同于菲涅尔反射的现象及其分析

本文导出了光折变位相共扼镜表面反射与共轭反射率以及双波耦合增益长度积的关系式．给出了ＢａＴｉＯ３晶体位相共扼镜的相对光强反射比随共轭反射率和入射角变化的实验结果，并分析了不同类型光折变晶体的位相共轭镜表面反射变化的不同情况．     

双掺杂LiNbO3晶体光谱和光折变特性

报道了双掺杂CeFe,CeMn,MnFe生长态LiNbO3(LN)的光谱及光折变效应二波耦合增益特性.研究表明,双掺杂浓度较高时,生长态的LiNbO3晶体的透过率光谱范围较小,光折变效应二波耦合增益较低.几种双掺杂晶体都比单掺Fe晶体的光折变效应二波耦合增益低,表现出较强的抗光折变特性.     

双掺杂LiNbO_3晶体光谱和光折变特性

报道了双掺杂Ce :Fe ,Ce :Mn ,Mn :Fe生长态LiNbO3(LN)的光谱及光折变效应二波耦合增益特性 .研究表明 ,双掺杂浓度较高时 ,生长态的LiNbO3晶体的透过率光谱范围较小 ,光折变效应二波耦合增益较低 .几种双掺杂晶体都比单掺Fe晶体的光折变效应二波耦合增益低 ,表现出较强的抗光折变特性     

光折变晶体中写入阵列平面波导实验

进行了在光折变晶体中写入阵列平面光波导的实验研究,分别给出了在LiNbO3∶Fe晶体和SBN∶Cr晶体中写入阵列平面光波导的实验结果.实验结果表明,用这种方法写入阵列平面光波导简便可行.     

温度对KNSBN晶体二波耦合增益的影响

对３００Ｋ至４２０Ｋ温度范围内的光折变晶体ＫＮＳＢＮ（钾钠铌酸锶钡）的前向二波耦合特性进行了实验观测和理论分析,结果表明,光增益不仅取决于实验的几何配置而且对温度有较大的依赖性,由室温提高温度至３６０Ｋ可提高放大倍数一倍以上     

Ce:KNSBN光折变晶体两波耦合特性研究

采用Ar+ 514.5nm的o光和e光测量了Ce:KNSBN晶体两波耦合增益系数随写入光夹角的变化关系曲线 ,得到了Ce:KNSBN晶体的有效电荷密度、有效电光系数和电子 -空穴对抗率等参数.依据光折变理论对增益系数随写入光夹角变化关系实验数据进行了拟合 ,拟合曲线与实验结果符合较好     

双掺杂LiNbO3晶体光折变效应图像存储特性

研究了系列双掺杂(Ce：Fe，Mn：Fe，Ce：Mn)以及不同后处理态(生长态、还原态和氧化态)铌酸锂晶体的透过率光谱和光折变全息存储特性．实验结果表明高掺杂铌酸锂样品的透过率光谱范围较窄；氧化态样品具有较大的透过率光谱范围；还原态样品具有较大的光折变二波耦合增益特性．难于同时获得大的波耦合增益和图像存储质量．     

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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