双螺旋铰链环芳烃的紫外光谱和圆二色谱密度泛函理论研究

圆二色谱对分子基团的空间取向非常敏感,能够提供手性分子的三维结构信息,已成为探索手性分子空间绝对构型的有力工具.采用密度泛函理论(B3LYP/6-31G)方法,对R双螺旋铰链环芳烃的几何构型进行了优化,用TD-B3LYP/6-31G方法计算了它的紫外吸收光谱(UV-Vis)和电子圆二色谱(ECD),从微观角度对产生UV-Vis、ECD谱吸收的分子轨道电子跃迁进行了归属指认,解释了分子电子结构与光学活性的关系.计算的R型双螺旋铰链环芳烃的UV-Vis、ECD谱与实验结果吻合很好,ECD谱具有一个强的正性Cotton效应及2个较强的负性Cotton效应.预测了S型双螺旋铰链环芳烃的ECD谱.得出结论,ECD谱的吸收峰起源于在R型双螺旋铰链环芳烃分子的电子非对称转移跃迁,是电子跃迁的不对称性的光谱响应.     

Sporothriolide电子圆二色谱的理论计算及其绝对构型的确定

Sporothriolide(6-己基-3-亚甲基四氢呋喃[3,4-b]呋喃-2,4-酮)最早是从Sporothrix sp.(孢子丝菌)中发现的一种抗真菌化合物。经核磁共振谱图解析,发现它是一个聚酮化合物;其化学结构中含有3个手性碳中心;并具有两种相对构型,即(3a S,6R,6aR)和(3aR,6S,6a S)。为了确定绝对构型,采用含时密度泛函方法,在MPW1LYP/6-31G(d,p)水平上计算了电子圆二色谱。通过与实测谱图的比对,其绝对构型被确定为(3a S,6R,6aR)。五元环的左手构象和右手构象产生了镜像对称的电子圆二色谱,表明五元环的构象翻转对其圆二色谱具有重要影响。此外,溶剂甲醇与sporothriolide之间的分子间氢键导致了低于14.1 nm的Cotton效应偏移,及低于75 cgs的峰强度的增强,说明溶剂化效应对sporothriolide的圆二色谱影响不大。     

通过Bergman环化聚合反应合成侧链含有苯丙氨酸的手性聚合物

合成了侧链带有手性氨基酸基团的烯二炔化合物,利用烯二炔化合物在加热或者光照条件下能够发生Bergman环化反应生成双自由基这一特点,制备了侧链含有手性中心的手性聚合物。红外光谱和核磁共振结果证实该烯二炔化合物发生了Bergman环化反应,凝胶渗透色谱结果证实获得了高分子量聚合物,圆二色光谱结果证实通过Bergman环化反应制备的聚合物具有主链手性。     

乙醛正丙硫醇缩醛的合成

以 0 .1 mol乙缩醛和 0 .1 mol正丙硫醇为原料 ,35℃下在四氯化碳中反应 ,经红外光谱 ,色谱 ,质谱 ,元素分析以及核磁共振谱检测 ,确证了产物为乙醛正丙硫醇缩醛 .产率为 72 % .产品含量为 99.7% .     

6-位脂肪胺取代的萘酰亚胺衍生物与DNA的相互作用

利用紫外可见光谱、荧光光谱、圆二色谱和粘度测试,考察了8个6-位脂肪胺取代的萘酰亚胺衍生物与小牛胸腺DNA的相互作用.研究结果表明:小牛胸腺DNA对与其结合能力强的化合物3a～3d有荧光猝灭作用,对与其结合能力弱的3e～3h有荧光增强效应;圆二色谱显示这些萘酰亚胺化合物能引起DNA二级结构发生不同的变化.在紫外-可见吸收光谱和粘度测试中,这些化合物与DNA的相互作用没有差别.综合光谱学和粘度测试的结果,推断这些化合物是通过嵌插方式与DNA结合,由于结构不同,它们与DNA之间作用程度存在差异.     

TATP炸药特性的红外光谱理论研究

利用b3lyp/6—31G(d)和b3lyp/6—31++G(d)的方法对TATP和TATP+的结构和红外振动光谱的特点进行了研究,并确定了分子的电离能。研究发现根据分子振动类型的不同,TATP的红外振动光谱主要分布在六个不同区域,且光谱中出现了简并和无红外活性的现象。与TATP分子的红外振动光谱相比,TATP+的红外振动光谱在相同区域中谱线的数目和强度都有了较大的不同。此外,TATP+光谱中最强峰和次强峰的位置与TATP分子相比出现了明显的红移现象。     

木榄的质量标准研究

为了建立海洋药物木榄(Bruguiera gymnorrhiza (Linn.)Savigny)的质量标准,以便为其质量控制提供参考,本研究采用薄层色谱法对木榄样品进行定性鉴别,并测定样品的水分、灰分和浸出物,采用分光光度法测定木榄中总黄酮含量。薄层色谱结果显示,在对照品(芦丁)色谱相应位置上显相同颜色的荧光斑点;木榄样品水分含量为7.95%～10.53%,总灰分含量为8.53%～9.52%,醇溶性浸出物(热浸法)的含量为13.05%～16.14%;总黄酮含量为33.36～37.57mg/g。据此初步拟定木榄的质量标准:水分含量不得超过12.0%、总灰分含量不得超过11.0%、醇溶性浸出物(热浸法)含量不得低于12.0%、总黄酮含量不得低于3.0%。制订的标准可用于木榄药材的质量控制。     

含玻璃相固体废物蒸压反应特性的红外光谱研究

通过红外光谱、X射线衍射、扫描电镜等手段研究了粉煤灰、废玻璃和矿渣等固体废物-石灰体系的蒸压反应特性。结果表明,1.2MPa饱和蒸汽压下,固体废物红外光谱强吸收区Si-O伸缩振动频率越低,其蒸压样品的结合水量越大,水热反应能力越强。粉煤灰、废玻璃的红外光谱强吸收区Si-O伸缩振动频率越低,其蒸压样品的强度越大。矿渣蒸压样品的强度与矿渣红外光谱强吸收区Si-O伸缩振动频率表现出不同于其他两种固体废物的规律,矿渣中铝参与反应形成大量的水石榴石,导致其蒸压样品的强度下降。     

手性二茂铁氨基醇的合成及表征

从二茂铁和天然光学活性氨基酸出发,合成了两个新型的手性二茂铁氨基醇,它们的结构通过了核磁共振谱,红外光谱,元素分析表征.     

长清产栝楼3个品系果皮水提取物红外光谱的三级鉴定

采用红外光谱三级鉴定法,对长清产3个品系栝楼果皮水提取物进行分析。实验结果表明,一维红外光谱和二阶导数红外光谱部分吸收峰的峰形、峰位和峰强具有一定的差异,二维相关谱中自动峰的峰数、峰位和峰强均有明显的区别。红外光谱三级鉴定法可以快速、准确地分析与鉴定3个品系栝楼果皮。     

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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