用阳离子置换法制备汞系高温超导薄膜

介绍了最近发明的一种制备汞系高温超导薄膜的新方法—阳离子置换法．采用Ｔ１ 系外延超导薄膜作为先驱薄膜,将Ｔ１ 系超导薄膜在Ｈｇ 气氛下进行热处理,用Ｈｇ 置换先驱薄膜中的Ｔ１,进而生成Ｈｇ 系外延超导薄膜．用此方法,成功地在ＬａＡｌＯ３ （００１）衬底上制做出了高质量的ＨｇＢａ２ＣａＣｕ２Ｏｘ 超导薄膜．Ｘ－光衍射θ－２θ扫描和极图测试表明,薄膜具有很纯的超导相和很好的外延结构．超导临界温度可达１２２Ｋ．在７７Ｋ温度下,临界电流密度达到３．４×１０６ Ａ／ｃｍ ２,在１１０Ｋ 温度下,临界电流密度仍可保持在０．７×１０６Ａ／ｃｍ ２ ．     

Tl_2Bg_2Ca_2Cu_3O_x单相超导块材的制备

本文研究了Ｔｌ＿２Ｂａ＿２Ｃａ＿２Ｃｕ＿３Ｏ＿ｘ（简称２２２３）单相超导块材的制备工艺。Ｘ射线衍射谱的分析和交流磁化率测量结果表明，对于名义组分为Ｔｌ＿２Ｂａ＿２Ｃａ＿２Ｃｕ＿３Ｏ＿ｘ的配料，在相当宽的温度范围（８７５℃～９５０℃）内烧结都有２２２３相生成。在８９７℃烧结２ｈ得到了纯的２２２３单相样品，其Ｔｃ（Ｒ＝０）值达１２０Ｋ。     

Hastelloyc—275上激光沉积YBCO超导线材

室温下应用Ａｒ＾＋离子源辅助准分子脉冲激光沉积取向的ＹＳＺ过渡层薄腊地ＮｉＣｒ合金基底上；基底加温至７５０℃，用分子脉冲激光高温超导薄膜于ＹＳＺ／ＮｉＣｒ上，并切割一材，实验结果表明：ＹＢＣＯ超导线材不但为ｃ－轴取向的，同时为在ａ－ｂ平面内织构的，其临界温度Ｔｃ≥９０Ｋ，临界电流密度Ｊｃ≥１×１０＾６Ａ／ｃｍ＾２（７７Ｋ，０Ｔ）。     

Hastelloyc-275上激光沉积YBCO超导线材

室温下应用Ａｒ＋ 离子源辅助准分子脉冲激光沉积 （０ ０ ２） 取向的 ＹＳＺ过渡层薄膜于ＮｉＣｒ 合金基底上;基底加温至７５０ ℃,用准分子脉冲激光沉积ＹＢＣＯ 高温超导薄膜于ＹＳＺ／ＮｉＣｒ 上,并切割成线材．实验结果表明：ＹＢＣＯ 超导线材不但为ｃ－轴取向的,同时为在ａ－ｂ 平面内织构的,其临界温度Ｔｃ≥９０ Ｋ（Ｒ＝ ０）,临界电流密度Ｊｃ≥１×１０６ Ａ／ｃｍ ２（７７ Ｋ,０ Ｔ）．     

高T_cBi（Pb）－Sr－Ca－Cu－O体系超导体的合成和研究

介绍高ＴｃＢｉ（Ｐｂ）－Ｓｒ－Ｃａ－Ｃｕ－Ｏ体系超导体的合成、测试，进行结构与超导性能关系研究，认为结构的稳定性和有序度对Ｂｉ－２２２３相的生成和超导性能有很大的影响。     

工业钢瓶中乙炔固定相溶解方法的研究

本文对工业钢瓶中乙炔固定相溶解方法进行了深入的究。在３５３Ｋ温度下，加６．０ｏｌ·Ｌ－ＩＨＢ（ｍ酸：ｍ样＝２０：１）和适量添加剂Ａ＋Ｂ＋ＮａＣ１（ｍ添：ｍ酸＝１：２０），反应６０ｍｉｎ。可使固定相（ＣａｓｉＯ３）中阳离子（Ｃａ２＋）溶出，而阴离子（ＳｉＯ（３２－）成为溶胶。该项研究成果为新的石油化学产品在我国应用推广及乙炔工业钢瓶的再生利用提供了可行途径。     

脉冲式XeCl激光辐照a－Si∶H膜诱导晶化的研究

当脉冲辐照ａ－Ｓｉ∶Ｈ膜的ＸｅＣｌ激光能量密度在２４０ｍＪ／ｃｍ￣２以上时，可引起被辐照膜发生明显的固相晶化；通过拉曼（Ｒａｍａｎ）散射谱、扫描电子显微照象（ＳＥＭ）和紫外（ＵＶ）分光光度吸收谱的实验，研究了不同辐照条件、不同膜厚及各种膜结构试样的晶化效果；还研究了使用ＣＯ＿２激光退火对被辐照膜的影响。结果表明，晶化膜的晶粒大小在０．１～１．０μｍ时，Ｒａｍａｎ位移为５１０ｃｍ￣（－１）～５１７ｃｍ￣（－１）、半峰高宽度为１０ｃｍ￣（－１）～１５ｃｍ￣（－１）；ａ－Ｓｉ∶Ｈ膜经ＸｅＣｌ激光辐照或ＣＯ＿２激光退火后，都会增强晶化膜的吸收效率。     

高临界电流密度外延T12Ba2CaCu2O8超导薄膜

本文用直流磁控离子溅射及后热处理工艺在（００１）ＬａＡ１０３单晶衬底上制备的Ｔ１２Ｂａ２ＣａＣｕ２Ｏ８高温超导薄膜，经Ｘ－光衍射θ－２θ和Φ扫描测试证明，薄膜是外延生长的。薄膜的超导转变温度高达１０８．６Ｋ。在液氮温度下，零磁场时的临界电流密度达７．６×１０６Ａ／ｍ２。薄膜具有很强的磁通钉扎能力。当垂直于膜面外加一个４特斯拉的磁场时，临界电流密度仍可保持１．１×１０６Ａ／ｃｍ２。     

高性能InP／InP,InGaAs／InP体材料LP—MOCVD生长

给出利用低压金属有机化合物化学汽相沉积（ＬＰ－ＭＯＣＶＤ）生长技术在ＩｎＰ衬底上生长ＩｎＰ、ＩｎＧａＡｓ的条件，研究了ＩｎＰ／ＩｎＰ的生长特性、ＩｎＧａＡｓ／ＩｎＰ的组份控制、生长特性及生长温度对ＩｎＧａＡｓ特性的影响．发现ＩｎＧａＡｓ／ＩｎＰ最佳生长温度为６４０℃，得到ＩｎＧａＡｓ／ＩｎＰ１６Ｋ光荧光（ＰＬ）谱全高半峰宽为３２．０ｎｍ，ＩｎＰ／ＩｎＰ室温霍尔迁移率为４３６０ｃｍ２／Ｖｓ，背景掺杂浓度为５×１０１４ｃｍ－３，Ｘ光双晶衍射全高半峰宽为２１＂．     

Bi系银基带材的制备微结构与性能的关系

采用分析纯原料进行粉末装管拉丝，然后用每道次变形量大于３０％的轧制工艺，经一次压制，在８２０～８８０℃之间非线性控制温度时间函数，总烧结时间少于１２０ｈ，制备出电流密度Ｊ＿ｃ（７７Ｋ，０Ｔ）大于３×１０￣４Ａ／ｃｍ￣２、波动范围在±２０％的高温超导Ｂｉ系银基带材，粉末装管后预抽真空处理和缓慢升温避免了长带材的起泡．ＤＴＡ研究表明，掺Ａｇ的带材降低了液相形成温度，提高了相分解温度，且使相变更易控制．ＳＥＭ显示非超导相为弥散细小的ＳｒＣａＣｕＯ。     

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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