非晶的激波晶化与高压变态对比研究

研究了非晶合金Ｆｅ７８Ｂ１３Ｓｉ９ 、（Ｆｅ０９９ Ｍｏ００１）７８Ｂ１３Ｓｉ９ 的激波晶化特点． 用Ｃｌｕｓｔｅｒ 模型讨论了在激波作用下晶化相的形成, 并把激波晶化与非晶高压变态作了比较． 为了更好地理解激波与非晶合金的相互作用, 还需要更进一步的实验工作和理论研究     

激波作用下三种铁基非晶合金的纳米晶化

在气体激波管中，利用激波对非晶的直接作用，在微秒量级时间内，成功地将ＦｅＢＳＩ，ＦｅＭｏＢＳｉ及ＦｅＣｕＮｂＢＳｉ等非晶合金转变成为纳米晶，主晶化相晶粒平均尺寸在２０－６０ｎｍ范围，晶化相分数〉９５％和常规退火晶化比较，激波晶化在晶化相，晶化动力学和晶化机理等方面具有一系列独有的特点。     

快淬NdFeB永磁合金的晶化行为

采用动态差示扫描量热法（ Ｄ Ｓ Ｃ） 和 Ｘ 射线衍射法（ Ｘ Ｒ Ｄ） 研究了快淬 Ｎｄ Ｆｅ Ｂ合金的晶化行为。非晶态 Ｎｄ８ ．５ Ｆｅ８６ Ｂ５ ．５ 合晶化由三个过程组成,各转变有效晶化激活能分别为４ ．８ｅ Ｖ、１５ ．２ｅ Ｖ 和５ ．４ｅ Ｖ。非晶态 Ｎｄ７ ．５ Ｄｙ１ Ｆｅ８５ Ｂ４５ Ｇａ２ 合金直接由非晶态转变为α－ Ｆｅ和 Ｎｄ２ Ｆｅ１４ Ｂ 相,有效晶化激活能为５ ．８ｅ Ｖ。     

非晶晶化法制备纳米晶双相永磁合金的磁性

采用快淬及退火工艺,通过非晶晶化制备了两种成分的纳米晶,即Ｎｄ２Ｆ３１４Ｂ／α－Ｆｅ永磁合金。研究了添加Ｄｙ＋Ｇａ和晶化工艺对合金磁性能的影响,研究结果表明,三元Ｎｄ８．５Ｆｅ８６Ｂ５．５合金晶化是由３个过程组成的,而添加Ｄｙ＋Ｇａ的Ｎｄ７．５Ｄｙ１Ｆｅ８５Ｇａ２合金化是由２个过程组成的,与三元合金相比,添加Ｄｙ＋Ｇａ可改变α－Ｆｅ和Ｎｄ２Ｆ１４Ｂ相的形成温度及细化两相晶粒,可以显著提高合金的磁性     

纳米晶Ti—Fe—Ni合金机械合金化的研究

应用ＸＲＤ，ＴＥＭ，ＤＳＣ等实验方法研究了第三组元Ｎｉ对Ｆｅ－Ｔｉ二元混合元素粉机械合金化反应的影响．试验中原子数百分比分别以５％和１５％Ｎｉ取代部分Ｆｅ元素．研究结果表明固态合金化合成晶粒尺寸分别为１２ｎｍ和６ｎｍ的纳米晶Ｂ２相．合金化中经历球磨“退火”过程，微观点阵畸变逐渐减弱，晶粒长大．Ｎｉ元素能使合成的Ｂ２结构纳米晶ＴｉＦｅ相的点阵畸变减小．合成的纳米晶相在９７３Ｋ产生相分解，析出低温马氏体ＴｉＮｉ相     

Fe78B13Si9非晶合金纳米晶化的亚结构

用高密度脉冲电流处理Ｆｅ７８Ｂ１３Ｓｉ９非晶合金，随电流密度的变化在不同的温度下和相同的时间内实现了试样的纳米晶化，透射电镜观察及Ｘ射线衍射分析表明，在由电脉冲方法所制备的纳米晶Ｆｅ７８Ｂ１３Ｓｉ９合金中存在着亚晶和孪晶等亚结构，三种晶化相是α－Ｆｅ（Ｓｉ）Ｆｅ２Ｂ和少量的Ｆｅ３Ｂ．随着电流密度的增加，试样中Ｆｅ２Ｂ相略有增加并出现了有序的Ｆｅ３Ｓｉ结构，但平均晶粒尺寸保持不变，由Ｓｈｅｒｒｅｒ方     

铁基非晶态合金晶化过程激活能的测定

阐述了Ｏｚａｗａ图法和Ｋｉｓｓｉｎｇｅｒ图法在测定铁基非晶态合金晶化过程激活能方面的应用，在满足不同加速率下的晶化温度所对应的晶化程度相同的前提下，用Ｏｚａｗａ图法和Ｋｉｓｓｉｎｇｅｒ图法测出的非晶态Ｆｅ７９Ｂ１６Ｓｉ５合金预晶化相α－Ｆｅ析出阶段的激自觉自愿能分别为３８２～４０７Ｋｊ／ｍｏｌ（Ｏｚａｗ图法）和３７４～３３９Ｋｊ／ｍｏｌ（Ｋｉｓｓｉｎｇｅｒ图法）测定结果十分接近，说明上述２种方法测     

磁记录用的BaFe_（12－2x）CoxTixO_（19）微粉的晶化特性研究

采用玻璃晶化法制备适合磁记录用的Ｃｏ－Ｔｉ替代型钡铁氧体ＢａＦｅ_（１２－２ｘ）Ｃｏ_ｘＴｉ_ＸＯ_（１９）（ｘ＝０，０．５，０．６，０．７，０．８，０．８５，０．９）微粉。动态（变温）Ｘ射线衍射和ＤＴＡ曲线分析表明，在非晶薄片基体的晶化过程中，随热处理温度的升高，首先晶化出ＢａＢ_２Ｏ_４和Ｂａ_２Ｂ_２Ｏ_７相，随后出现钡铁氧体相；温度到达８５０℃后，非磁性相消失，仅剩有磁性的钡铁氧体相．晶化过程为先成核而后长大。有关晶化条件对钡铁氧体微粉粒子尺寸及分布的影响、对形貌的影响也作了详细的探讨。     

添加Dy和Nb的纳米复合Pr2Fe14B/α-Fe永磁合金结构和磁性

研究了添加Ｄｙ和Ｎｂ对纳米复合Ｐｒ２Ｆｅ１４Ｂ／α－Ｆｅ永磁合金形成,组织结构及磁性的影响。结果表明：Ｐｒ９Ｆｅ８５Ｂ６非晶带的晶化过程,在α－Ｆｅ相初始晶化之后,出现Ｐｒ２Ｆｅ２３Ｂ３亚稳相,最终形成Ｐｒ２Ｆｅ１４Ｂ＋α－Ｆｅ两相组织．而添加Ｄｙ或同时添加Ｄｙ和Ｎｂ后晶化过程不出现亚稳相．添加Ｄｙ和Ｎｂ元素显著地提高了纳米复合永磁合金的磁性能。最终获得了磁性能为Ｈｃｉ＝７０２．４ｋＡ／ｍ,Ｂｒ＝１．０３Ｔ,（ＢＨ）ｍａｘ＝１３２．６ｋＪ／ｍ３的纳米晶复合Ｐｒ８Ｄｙ１Ｆｅ８４Ｎｂ１Ｂ６永磁材料。     

Ni82.5Cr7Si4.5B3Fe3多元非晶态合金钎料的晶化行为及其真…

采用示差扫描量热计（ＤＳＣ）和Ｘ射线衍射方法研究了Ｎｉ８２．５Ｃｒ７Ｓｉ４．５Ｂ３Ｆｅ３多元非晶态合金钎料在加热时的晶化特性。实验指出：随加热速率的增大，其晶化特征温度逐渐提高，晶化前所需孕育时间延长，并且晶化后的二次相变过程消失；探讨了该钎料的真空钎焊工艺性能和钎焊接头力学性能，以及预晶化处理对它们的影响，并与相同成分的粉状和粘带状晶态钎料进行了系统的比较。研究结果指出：非晶态钎料在工艺性能方面     

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     

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