伸长法测金属丝杨氏模量实验的改进

自制了一种测量微小位移的传感器，用于测量金属丝的伸长量，进而测出其杨氏模量，和传统的测量杨氏模量的其它方法相比较，这种方法是一种电测法，明显、直观、误差小，具有极大的优越性。     

纳米材料杨氏模量的测量

报道了利用激光超声技术测量纳米材料杨氏模量的测试方法。根据测量声波在材料内传播的时间和试样的厚度，确定声波在材料内的传播速度，进而由材料的密度即可计算出材料的杨氏模量；并对不同烧结温度下纳米氧化锆进行了测量，结果表明纳米氧化锆的杨氏模量随烧结温度的升高而增加，此方法简便实用，并对试样的形状无特殊要求。     

胡克定律实验新探

本论文从胡克定律验证实验的图像出发，分析了杨氏模量和弹性衡量之间的关系，运用传感器测量杨氏模量的方法间接地验证和讨论了胡克定律的使用范围。     

拉伸法测杨氏模量的改进

通过对测试试件（金属丝）的横向受力分析，建立了试件偏转角度与试件杨氏模量之间的一般表达式。在此基础上，对拉伸法测杨氏模量的实验装置进行重新设计，实现了仅通过对试件直径、受力后的角度偏转量的测量完成对试件杨氏模量的确定。测量条件宽松，测量精度高，克服了目前常采用的纵向拉伸测杨氏模量存在的实验装置笨重、复杂、辅助工具多、测量数据多的缺陷。     

材料杨氏模量的激光干涉式测量

建立了一种材料杨氏模量的激光干涉测量系统，并以碳钢材料为例，对这一系统的精度进行验证，将实测值与材料杨氏模量的标准值进行了比较，结果表明，使用激光干涉式系统测量材料的杨氏模量其精度提高到千分位。     

电容传感器法测量钢丝的杨氏模量的应用研究

研究了利用电容传感器法测量钢丝的杨氏模量的新方法，该法利用电容传感器的输出电压随极板间的距离的变化关系式来测量杨氏模量。将电容传感法和光杠杆法测量钢丝的杨氏模量的结果进行了对比，结果表明，两的测量结果十分相符。电容传感器法具有快速、简便、易于掌握的优点。     

杨氏弹性模量的光学测量法

对杨氏模量的测量,传统方法的精度往往达不到测量要求。提出一种用迈克耳逊干涉仪及计数器测杨氏模量的新方法;并通过实验测量金属丝的杨氏模量证明了该方法的可行性。     

利用激光测量金属丝杨氏模量的实验研究

利用激光直射法和反射法对传统的杨氏模量测量方法进行实验改进,实验表明：应用这两种方法测量碳钢丝的杨氏模量,所得测量结果与标准值吻合较好．相对于杨氏模量传统测量方法来说,利用激光测量金属丝杨氏模量不仅调节方便,而且直观性强,准确度高．是对现有光杠杆法测量杨氏模量实验的一种补充和完善．     

自由振动法测量材料杨氏模量

根据振动理论，给出了悬臂梁自由振动的周期与材料杨氏模量的关系，并设计了一种测量材料杨氏模量的实验装置，该装置的测量精度比传统的静态拉伸法高一个数量级。     

一种改进的扬声器CAD系统

在分析以往数值研究扬声器模型的基础上，编制了扬声器的计算机辅助设计软件，该软件作了两个重要改进，其一是采用振膜杨氏模量不均匀模型，相应配套研制了振膜分布杨氏模量的自动测量系统；其二是全面了声负载问题，实测结果证帝了上述方法和模型是正确的。最后对变杨氏模量问题的声负载问题作了讨论。     

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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