NAB晶体改性研究

报导了LaxN_(1-x)AB晶体的生长;测量了其折射率、吸收光谱和荧光光谱。掺入不同量的 La~(3+)离子,其荧光寿命比NAB晶体增加18.4％。用染料激光器泵浦,观测了其激光输出性能。     

硼酸铝钕晶体中钕离子的电声子耦合S因子

利用黄昆公式和晶格场动力学参数与静晶场参数的关系估算了硼酸铝钕(NAB)激光晶体中钕离子的 S 因子。进一步讨论了 Auzel 关于自激活激光晶体浓度猝灭效应准则的深层含意.     

作为NAB助熔剂的钼酸钾体系的研究

本文研究了各种多钼酸钾合成的过程和产物,以及各助熔剂体系在不同温度下的挥发速率;求得反应速率常数,确定在高温下K_2Mo_3O_(10)和K_2Mo_4O_(13)的分解反应为零级反应,其活化能分别为130.8和191.5KJ/mole。并研究了各多钼酸钾助熔剂体系对NAB晶体生长的影响,通过比较,认为以K_2Mo_3O_(10)为主的助熔剂体系为多钼酸钾系列中生长NAB晶体最好的助熔剂体系。     

溶剂蒸发法制备CH_3NH_3PbI_3晶体及其光吸收特性

为了研究采用直接蒸发溶剂法制备所得CH_3NH_3PbI_3晶体的结构和光吸收特性,利用X线衍射、扫描电子显微镜、紫外-可见吸收光谱、介电频谱测试和分析样品的晶体结构、微观形貌、光吸收性能和介电性能.结果表明:采用溶剂蒸发法可以快速获得立方相结构的CH_3NH_3PbI_3晶体,将样品放入无水乙醚中密封保存后,真空条件下所得晶体的介电损耗随着频率的升高变化明显,而介电常数相对较为稳定,此外,制备所得CH_3NH_3PbI_3晶体的光吸收度良好.研究说明由溶剂蒸发法获得的立方相CH_3NH_3PbI_3晶体可以作为钙钛矿太阳能电池光吸收层的优质原料.     

三角晶场中3d^3离子精细光谱结构和局域结构的关系

目的研究三角晶场中3d3离子光谱精细结构和晶体局域结构之间的关系。方法利用自旋哈密顿理论,采用对角化能量矩阵的方法。结果计算了YAG：Cr3＋晶体的光谱精细结构和键角之间的关系。结论三角晶场中3d3离子基态能级分裂对晶格局域结构变化非常敏感,而其它激发态能级对晶格局域结构不很敏感。     

三角晶场中3d3离子精细光谱结构和局域结构的关系

目的 研究三角晶场中3d3离子光谱精细结构和晶体局域结构之间的关系.方法 利用自旋哈密顿理论,采用对角化能量矩阵的方法.结果 计算了YAG:Cr3 晶体的光谱精细结构和键角之间的关系.结论 三角晶场中3d3离子基态能级分裂对晶格局域结构变化非常敏感,而其它激发态能级对晶格局域结构不很敏感.     

NaCaF3晶体的电子结构及光学性质

基于第一性原理超软赝势平面波方法,对钙钛矿结构NaCaF_3晶体的电子结构与光学性质进行了研究.对NaCaF_3晶体的结构进行了几何优化,计算了其能带结构、态密度、介电函数、能量损失函数、反射光谱和吸收光谱,获得了相关的光学性质.研究结果表明NaCaF_3晶体是间接带隙化合物并具有宽带隙,而且表现出光学各向异性,其光反射峰值的位置和能量损失函数计算的结果相吻合,光学吸收边在4.989 e V处.此外,根据介电函数虚部的色散关系可推断出其在较高能量的光谱范围内具有良好的透过率.     

Ba、Gd共掺杂SrTiO3结构的能带计算

运用第一性原理密度泛函理论研究了未掺杂、Ba掺杂和Ba、Gd共掺杂SrTiO3(STO)晶体的几何结构、能带结构、电子态密度,并且进行了分析.计算结果表明,未掺杂的STO、Ba单掺杂和Ba、Gd共掺杂STO晶体的禁带宽度分别为1.89ev、1.77ev、0.677ev,同未掺杂、Ba单掺杂STO相比,Ba、Gd共掺杂STO晶体具有更稳定的结构,更窄的带隙,并且呈现出导电性.     

在绿柱石晶体中掺入Fe^3＋的吸收光谱研究

绿柱石是一种结构较复杂的硅酸盐矿物,其晶体结构中Al^3＋可以被Fe^2＋,Fe^3＋等取代,对这种晶体的吸收光谱的研究有助于认识绿柱石晶体的结构,从而更好的使这种晶体得到应用．本文引入平均共价因子Ⅳ,在立方晶场下考虑电子静电相互作用,通过完全对角化的方法对掺入Fe^3＋的绿柱石晶体的吸收光谱进行理论计算,并对实验结果中吸收峰进行了识别．结果表明,实验与理论符合的比较好．     

EuPdGe3磁性与电子结构的第一性原理计算

为了探究EuPdGe3晶体材料的基态性质和磁晶易轴方向,本文采用基于密度泛函理论的VASP软件包计算研究了EuPdGe3材料的磁性与电子结构。计算结果表明EuPdGe3基态磁构型为A型反铁磁,磁晶易轴方向沿c轴方向。通过对EuPdGe3晶体的电子结构和实空间结构分析,得出了Ge2 4p电子态与Eu 4f电子态间的杂化是EuPdGe3晶体磁晶易轴方向沿c轴的原因。     

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.     

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     

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