四苯乙烯基荧光探针的合成及对硝基爆炸物的检测

基于四苯乙烯的聚集诱导发光(AIE)性质,设计合成了一种可用于硝基爆炸物检测的荧光探针分子S1.采用核磁氢谱、碳谱和高分辨质谱对其结构进行表征后,以4-硝基苯酚为模型化合物,利用紫外可见分光光度计和荧光光谱仪对S1进行爆炸物检测,结果发现此荧光探针分子S1的检测极限可低达4.59μmol/L.     

一种2-肼基苯并噻唑衍生物作为Ag+荧光探针的研究

本论文利用2-肼基苯并噻唑与2-氰基苯甲醛缩合，获得了一种席夫碱型荧光化合物，它能够在水体系中高选择性、高灵敏度荧光识别Ag+离子.利用质谱分析、核磁共振方法对其的结构进行了表征，并利用紫外可见光谱、荧光发射光谱详细研究了该探针与Ag+ 相互作用的光谱性能.实验结果表明，随着Ag+浓度的增加，该探针的紫外-可见吸收光谱峰发生20 nm的红移，同时，其荧光强度逐渐增强，该探针表现出比色和荧光增强双重识别作用.     

一种基于萘异硫氰酸酯的Hg2+反应型荧光探针

以萘异硫氰酸酯为反应基团和荧光基团,设计、合成了一种能够识别Hg2+的荧光探针（HBN）,利用质谱、核磁共振方法表征了其结构,并利用紫外-可见吸收光谱、荧光发射光谱,对HBN识别Hg2+的性能进行了测试及分析.研究发现,HBN在50%乙腈水溶液中对Hg2+表现出非常高的选择性和灵敏度,其荧光强度随Hg2+浓度的增强而不断增强,当Hg2+浓度为探针浓度2倍时荧光强度不再上升,同时质谱检测到新物质的生成,显示了该探针属于Hg2+反应型荧光探针。     

聚对苯乙烯撑型超支化共轭聚合物的合成及荧光淬灭研究

通过Heck缩聚反应合成了2种以三苯胺为核的"A2 B3"聚对苯乙烯撑型超支化共轭聚合物.通过FT-IR,1HNMR,GPC和TGA等测试对聚合物进行了表征.此类超支化聚合物具有良好的溶解性和热稳定性.通过紫外吸收光谱,荧光发射光谱表征了聚合物的光化学性能,并首次对含硝基芳香烃淬灭其溶液荧光的能力进行了初步研究.此类聚合物不仅合成较为容易,检测的灵敏度也较高,是一类潜在的检测含硝基芳香烃爆炸物的荧光传感器材料.     

一种香豆素-吲哚类氰离子荧光探针的理论研究

为了开发新型氰离子荧光探针,采用量子化学计算方法、密度泛函理论对一种新型香豆素-吲哚类荧光探针M~+_1及其与CN~-的加成物M_1-CN的优化构型、吸收光谱、激发光谱进行了研究,并讨论该探针应用于氰离子检测的光物理机制.结果显示:M~+_1最大发射光谱为766 nm,处于近红外区;M_1-CN的最大发射光谱为285 nm,该探针与CN~-加成后发射光谱发生了非常显著的蓝移;激发态下M~+_1和M_1-CN的前沿轨道形状差异较大.表明M~+_1可作为检测CN~-的高灵敏荧光探针,并可用于生物医学光学成像剂.     

基于含硫席夫碱衍生物的荧光增强型Hg2＋探针

文中设计合成了新的含硫原子的席夫碱（Schiff base）衍生物CzSB,该化合物可以作为荧光增强型Hg2＋探针.通过紫外-可见光吸收光谱和荧光发射光谱研究了探针CzSB对Hg2的响应过程,Hg2＋的加入显著增强探针的荧光发射.探针CzSB对金属离子的识别作用和竞争选择能力也经由荧光光谱进行了研究,结果表明该探针对Hg2＋具有较高的选择响应性并且不受其他常见金属离子的干扰.初步探讨了该探针分子与Hg2的结合模式和荧光增强机理,Job曲线表明探针CzSB与Hg2以1∶2计量比配位.     

基于氢键策略卟啉荧光探针的合成及其在2,4,6-三硝基苯酚选择性检测中的应用

考虑到苦味酸带来严重的社会安全和环境危害问题,发展快速、选择性痕量检测硝基芳烃爆炸物苦味酸的方法极为重要。本文结合密度泛函理论计算,设计合成带有脲基团的锌卟啉荧光探针分子用于含硝基芳烃的荧光检测;荧光测试结果证实带有脲基团的锌卟啉ZH-1能够快速、选择性检测苦味酸,荧光淬灭明显,其它一硝基芳烃、二硝基芳烃不能淬灭锌卟啉ZH-1荧光;锌卟啉ZH-1和苦味酸的核磁共振氢谱滴定实验证实脲基团与硝基之间存在明显的氢键作用,从而导致快速荧光响应。上述研究结果表明:氢键策略可应用于荧光探针分子设计用于苦味酸快速和选择性检测。锌卟啉ZH-1荧光探针结构经1H NMR、13C NMR和高分辨质谱表征。     

一种基于2-(2-羟基苯基)苯并噻唑近红外脂滴荧光探针的合成及细胞成像研究

以2-(2-羟基苯基)苯并噻唑为母体,通过缩合反应,将其与二氰基异佛尔酮相连接,合成得到一种近红外荧光探针LD-YK,并对其结构进行了氢谱表征.通过紫外-可见吸收与荧光发射光谱研究了探针LD-YK的光物理性质,结果表明探针LD-YK在不同溶剂中的最大荧光发射波长均超过650 nm,属于近红外区域,且具有较大的斯托克斯位移.细胞实验结果表明探针LD-YK具有较低的细胞毒性,且可靶向于细胞内的脂滴部位.     

苯肼类硫化氢荧光探针的构建及性质研究

以硝基取代苯肼和苯甲醛衍生物为原料,设计并合成了一系列含有苯肼类硫化氢荧光分子探针.通过紫外-可见光谱、荧光光谱等实验测定了探针与生物重要阴离子（HS^-,H₂PO■, AcO^-, F^-, Cl^-, Br^-, I^-）及硫醇（Cys, GSH, Hcy）的相互作用,分析了主客体可能的作用机制,筛选出具有高选择性和高灵敏度的荧光探针.结果表明,荧光探针1+Cu²⁺对HS^-的结合能力最强,且显示较高的选择性和灵敏度.此外,该探针对人肝癌细胞（HepG-2）的毒性较小,可为肝癌的早期诊断与预防提供重要依据.     

基于氟硼二吡咯的水溶性高灵敏汞离子荧光探针

以氟硼二吡咯作为荧光基团、以肼基作为活性基团设计、合成了一种可用于物质的量高灵敏地检测水溶液中汞离子的荧光探针(MS).该探针在水溶液中5 min内基本可以完成对汞离子的检测,随着汞离子浓度的增加,溶液紫外吸收明显红移,荧光强度大大增强.即使体系中汞离子物质的量浓度在0.1μmol/L时,溶液荧光强度也有明显变化,说明该探针具有很高的灵敏度.另外选择性实验表明该探针在相同条件下对其他常见金属离子没有明显响应,说明该探针具有很好的选择性.     

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     

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