溶胶-凝胶法制备掺钕钛酸铋铁电薄膜

采用溶胶-凝胶法在Pt／Ti／SiO2／Si基片上制备了掺钕(Nd)的Bi4Ti3O12薄膜(Bi4-xNdx)Ti3O12(x=0．85)，将薄膜于空气中710℃退火0．5h，形成BNT多晶薄膜。系统研究了薄膜的结构、电学性质、表面形貌、漏电流、疲劳特性等。结果表明薄膜呈(117)和(00l)的混合取向，显示良好的铁电性(2Pr=60．8μC／cm^2)，并呈现良好的抗疲劳特性。     

Gd掺杂对BiFeO3薄膜电性能的影响

采用溶胶-凝胶方法在FTO／glass底电极上制备了Gd掺杂BiFeO3薄膜。研究了Gd掺杂对BiFeO3薄膜的晶体结构、铁电性能和漏电流的影响．XRD测试表明薄膜获得良好的结晶。铁电性的测试表明,通过CA掺杂,使薄膜的铁电性得到了增强,剩余极化强度由50．1uC／cm^2增加到89．6uC／cm^2．     

预退火工艺对Bi3.15Nd0.85Ti3O12铁电薄膜性质的影响

采用溶胶一凝胶法在Pt／Ti／SiO2/Si基片上制备了Bi3.15Nd0.85Ti3O12铁电薄膜。将薄膜分别进行每一层预退火、每二层预退火、每三层空气中500℃预退火10min，分别称为a．b、c组薄膜，最后都于氮气氛中680℃总退火0．5h。结果表明，预退火工艺对薄膜的铁电性能影响较大，而对取向基本没有影响。同时，a,b两组薄膜的铁电性能（2Pr分别为47．8μC／cm2。和51．9μC／cm2）远远优于c组薄膜的铁电性（2Pr=28．7 μC／cm2）。所有Bi3.15Nd0.85Ti3O12薄膜都呈现良好的抗疲劳特性。     

新型存储材料BIT铁电薄膜B位双掺杂初探

利用化学溶液沉积法，在Pt／Ti／SiO2／Si（100）基底上和700℃条件下分别制备了Nd和（Al，Sc）共掺杂的钛酸铋薄膜（Bi3.15，Nd0.85）（Ti3-x（Alx，scx））O12[记做BNT（AI（x），sc（x））]（x=0．015，0．030，0．045，0．060），并进行了这一系列薄膜的微结构、表面形貌、铁电等特性的研究．发现当掺杂含量为x=0．030时，薄膜具有较高的剩余极化强度（2Pr=24．80／2C／cm2）．讨论了相关的物理机制．     

Nb掺杂对Bi3．25La0．75Ti3O12薄膜微观结构与性能的影响

采用Sol—gel法在p—Si和Pt／Ti／SiO3／Si衬底上制备了Bi3．25La0．75Ti3O12（BLTN）电薄膜,研究了Nb掺杂量对薄膜微观结构、介电和铁电性能的影响。结果表明：650℃退火处理的BLTN薄膜具有单一的层状钙钛矿结构,表面平整致密,且为随机取向;Nb掺杂量X在0．06的BLTN薄膜介电与铁电性能优良,剩余极化Pr和Ec分别为21．6℃／cm^2和96．8kV／cm,室温下,在测试频率为10kHz时,薄膜的介电常数为386．介电损耗为0．69％。     

利用脉冲激光剥蚀技术制备PZT铁电薄膜

利用脉冲激光剥蚀技术在抛光的硅片上制备出了Ｐｂ（Ｚｒ，Ｔｉ）Ｏ３铁电薄膜．经过淀积后的激光退火工艺，大大改善了这种膜的铁电性．研究了影响薄膜性能的多种因素，利用Ｘ射线衍射，分析了薄膜的结构．测量了薄膜的居里温度和电滞回线     

高性能CMOS LVDS I/O接口单元的设计研究

提出了一种适用于笔记本电脑平板显示器接口的高性能CMOS LVDS I／O接口单元，着重分析了高性能CMOS LVDS I／O接口单元电路结构及其工作原理，基于TSMC的3．3V0．25μm CMOS SPICE模型，在Cadence的环境下用Spectre仿真器进行模拟，仿真结果充分体现了该LVDS I／O接口单元的高速率、低功耗及低噪声等高性能．     

0.9Pb(Sc1/2Ta1/2)O3-0.1PbTiO3/0.65Pb(Mg1/3Nb2/3) O3-0.35PbTiO3 多层薄膜的制备及铁电性研究

以LaNiO3做缓冲层,用射频磁控溅射法在SiO2/Si(100)衬底上制备出0.9Pb(Sc1/2Ta1/2)O3 -0.1PbTiO3/0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3铁电多层薄膜.采用两步法在峰值温度650℃和700℃对薄膜进行退火.通过电滞回线和漏电流曲线对薄膜的铁电性能进行了测量.研究发现,650 ℃退火的薄膜有较好的铁电性,其剩余极化2Pr=9.5 μc/cm2,矫顽场2Ec=42.2 kV/cm,100 kV/cm场强下漏电流密度为31μA/cm2.700 ℃退火的薄膜铁电性有所下降,2Pr=3.1 μc/cm2,但薄膜却具有很低的矫顽场,2Ec=22.6 kV/cm.分析认为,铁电性的退化与高温下薄膜中异质结间的相互作用及挥发性元素Pb和Mg的损失密切相关.     

La0．67Ca0．33MnO3／YBa2Cu4O8／La0．67Ca0．33MnO3三效应研究层膜的时间

报导了La0．67Ca0．33MnO3／YBa2Cu4O8／La0．67Ca0．33MnO3薄膜中超导特性的时间效应。样品在空气中存放11个月后，超导转变温度都降低，而且每个系列样品的临界厚度增加。对用La0．67Ca0．33MnO3作保护层的YBa2Cu4O8薄膜进行时间效应测量，结果表明当La0．67Ca0．33MnO3层的厚度大于40nm时可以防止水对YBa2Cu4O8薄膜的影响。     

溶胶-凝胶法制备掺钕钛酸铋铁电薄膜及其性能

采用溶胶-凝胶法在FTO/glass 衬底上制备了Bi4 Ti3O12和Bi3.35Nd0.65Ti3O12 (BNT) 薄膜, 研究了Nd 掺杂对Bi4Ti3O12薄膜的晶体结构、铁电性能和介电常数的影响. XRD 研究表明Nd 掺杂未对薄膜的结晶产生显著的影响.铁电性的测试表明,通过Nd 掺杂,使薄膜的介电性和铁电性得到了增强,剩余极化强度由57.2 μC/cm2 增加到68.4 μC/cm2.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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