γ-环糊精-达旦黄包合物与鲱鱼精DNA的作用机理

在生理pH=7.4环境下,用摩尔比法测定γ-环糊精(γ-CD)与达旦黄(TY)的包合比(摩尔比)nγ-CD-nTY =1-1,直线法测定包合常数Kf = 495.23 L/mol.以中性红(NR)作分子探针,用紫外光谱法、荧光光谱法、电化学法、化学热力学法和黏度法等研究包合物γ-CD-TY与鲱鱼精DNA的作用,得到γ-CD-TY包合物与鲱鱼精DNA作用的结合比nγ-CD-TY-nDNA=6-1,结合常数为=1.12×105 L/mol,=2.72×105 L/mol.热力学函数=-2.82×104 J/mol,=5.67×104 J/mol,=284.78 J/(mol·K),说明γ-CD-TY包合物与DNA作用为熵驱动.确定γ-CD-TY与鲱鱼精DNA的作用方式为混合作用,同时存在部分嵌插和非嵌插作用方式.     

4-苄氧基苯酚与鲱鱼精DNA相互作用的研究

在pH=7.4的Tris-HCl缓冲溶液中,采用荧光光谱法、黏度法等分析方法研究了4-苄氧基苯酚(PBP)与鲱鱼精DNA的作用方式,用摩尔比法确定了PBP与DNA的结合比为2∶1。通过热力学研究得出,在27℃时PBP与鲱鱼精DNA之间相互作用的结合常数为Kθ300.15K=2.16×105L/mol,热力学函数ΔrHθm=-6.18×104J/mol,ΔrSθm=-1.05×103J/(mol·K),ΔrGmθ300.15K=-3.04×104J/mol,结果表明该反应为焓驱动。综合实验结果确定了PBP与DNA的作用方式为部分嵌插以及静电作用。     

异优呫吨酮及其衍生物与DNA相互作用的研究

采用紫外光谱、荧光光谱、圆二色谱以及红外差谱法研究了异优呫吨酮(1,6-二羟基吨酮)(A)及其哌啶衍生物(1-羟基-6-(2-(1-哌啶基)乙氧基)呫吨酮)(B)与小牛胸腺DNA(CT-DNA)的作用方式和作用强度。结果表明,这两种化合物的紫外吸收光谱随DNA浓度的增加表现出减色效应;化合物A和B与DNA作用的结合常数分别为1.5×104,2.8×104 L/mol;DNA-EB体系的荧光强度随着两种化合物浓度的增加发生淬灭现象,化合物A和B的淬灭常数Kq分别是1.9×104,3.7×104 L/mol;两种化合物主要以嵌入方式与CT-DNA发生作用,B与DNA的结合能力比A强;并且呫吨酮芳环的嵌入使DNA螺旋变得松散、碱基堆积增强;化合物B插入后使CT-DNA的构象变化更为明显。研究结果对抗肿瘤药物的研发有一定的指导意义。     

毛细管区带电泳测定两种生物碱与牛血清白蛋白的结合常数研究

采用毛细管电泳淌度移动法研究盐酸麻黄碱、磷酸可待因与牛血清白蛋白(BSA)的结合常数.使用未涂层弹性石英毛细管柱75μm×60cm(有效长度50cm),在pH 7.40、浓度25mmol/L Tris-HCl的电泳缓冲溶液及分离电压20kV,紫外检测波长214nm,温度37℃的条件下,测得盐酸麻黄碱、磷酸可待因与BSA的结合常数分别为1.46×104 L/mol和0.75×104 L/mol.该法简单、快捷,可用于研究结合比为1∶1的药物小分子与生物大分子的相互作用.     

茜素红S-钆(Ⅲ)配合物与DNA的相互作用

在pH 7.0的中性环境下,采用紫外光谱、荧光光谱研究了茜素红S(ARS)与稀土金属Gd(Ⅲ)形成的配合物Gd(Ⅲ)(ARS)3与鲱鱼精DNA的相互作用.同时,用摩尔比法和双倒数法测得配合物的配合比nARSnGd(Ⅲ)=31,Gd(Ⅲ)(ARS)3与DNA的结合常数K25℃=1.99×105L/mol,热力学函数△rHθm=-9.50×104J/mol,△rHθm=-3.02×104 J/mol,△rHθm=-217 J/mol·K.选择吖啶橙(AO)作为光谱探针,Gd(Ⅲ)(ARS)3与DNA-AO作用时,电子吸收光谱出现红移.荧光光谱研究表明Gd(Ⅲ)(ARS),能使DNA-AO发生静态猝灭,Scatchard图显示Gd(Ⅲ)(ARS)3配合物与鲱鱼精DNA之间存在着嵌插与非嵌插混合作用方式.     

光谱法研究杀螟丹与牛血清白蛋白相互作用

在模拟人体生理条件下,应用荧光光谱法及紫外可见光谱法研究农药杀螟丹与牛血清白蛋白(BSA)间相互作用的荧光行为,用同步荧光技术和圆二色谱考察杀螟丹对BSA结构影响。实验发现,杀螟丹对BSA有较强荧光猝灭作用,猝灭机制属于静态猝灭。用Stern-Volmer方程处理实验数据,得到298K、303K、308K和310 K时的结合常数分别为1.099×104 L/mol、0.805×104 L/mol、0.324×104 L/mol和0.200×104 L/mol,能量转移理论求得二者之间的结合距离是2.5nm;其结合作用力以氢键和范德华作用力为主;一些金属离子的存在会影响杀螟丹对BSA的作用;相互作用使BSA的结构发生改变.     

甲基丙烯酸-8-羟基喹啉-Eu(Ⅲ)配合物与鲱鱼精DNA的作用机制

采用光谱法、黏度法和DNA热变性方法研究甲基丙烯酸8羟基喹啉Eu(Ⅲ)配台物(Eu(MA)_2(hq))与鲱鱼精DNA之间的作用机制和结台常数结果表明:该配台物加人鲱鱼精DNA后,特征吸收峰发生明显的减色效应,但峰位红移现象不明显;该配台物能猝灭中性红DNA体系的荧光;该配台物与鲱鱼精DNA的结台常数K_(20)=5.91×10~3L/mol,K_(35)=7.70×10~3L/mol,二者作用的物质的量比为1;该配台物与鲱鱼精DNA之间的热力学函数△rH_m~e=1.34×10~3J/mol,△rG_m~e=-2.12×10~4J/mol,△rS_m~e=76.41 J/(mol·K);鲱鱼精DNA的相对黏度增大,熔点明显升高,Eu(MA)_2(hq)与鲱鱼精DNA之间的作用模式为插人作用.     

光谱法研究6-糠氨基嘌呤与牛血清白蛋白的相互作用

利用荧光光谱法、紫外光谱法、荧光寿命和圆二色光谱法等方法研究了6-糠氨基嘌呤(KT)与牛血清白蛋白(BSA)之间相互作用机理.结果表明,KT可以显著猝灭BSA的内源荧光,其猝灭机制为静态猝灭,猝灭常数Ksv在288 K和303 K时分别为1.45×104和1.42×104L/mol,Stern-Volmer曲线是两段相交于cKT=8.0×10-5mol/L的回归曲线,说明KT与BSA之间存在两类结合位点.数据处理及热力学参数计算表明:低浓度KT-BSA(cKT8.0×10-5mol/L)的结合主要是疏水作用,结合位点数约为1;较高浓度KT(cKT8.0×10-5mol/L)主要以氢键、范德华力与BSA结合,结合位点数为3.7.紫外光谱和圆二色光谱实验结果表明,KT的存在使BSA二级结构发生了改变.     

光谱法研究卟啉-蒽醌化合物及其金属锌配合物与DNA的相互作用

用光谱法研究以二肽链连接的卟啉-蒽醌化合物及其金属锌配合物与DNA的相互作用.结果表明:卟啉-蒽醌化合物及其金属锌配合物与DNA发生外部结合.由紫外-可见光谱滴定数据进行拟合计算出卟啉-蒽醌化合物及其金属锌配合物与DNA相互作用的结合常数分别为2.2×105(mol/L)-1和6.7×105(mol/L)-1.     

酪氨酸-钐(Ⅲ)配合物与鲱鱼精DNA的作用方式

采用UV光谱法、荧光光谱法,在pH=7.40的生理环境中用摩尔比法确定了Sm(Ⅲ)与Tyr(酪氨酸)结合的物质的量比n(Sm(Ⅲ)):n(Tyr)=1:3,Sm(Ⅲ)(Tyr)3配合物与hs(鲱鱼精)DNA结合的物质的量比n(Sm(Ⅲ)(Tyr)3):n(DNA)=3:1。用双倒数法确定了结合常数K2Θ98.15K=9.97×104L/mol和K3Θ10.15K=7.56×103L/mol。化学热力学研究显示配合物Sm(Ⅲ)(Tyr)3与hsDNA的结合过程为焓驱动;结合Scatchard法和黏度法,确定了配合物Sm(Ⅲ)(Tyr)3与hsDNA之间的作用方式为沟渠作用和嵌插作用。     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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