高半胱氨酸SAM膜电极的制备及其电化学行为研究

研究了高半胱氨酸在金电极上形成单分子自组装膜的条件，并利用循环伏安法，交流阻抗谱研究了[Fe(CN)6]^3-/4-在高半胱氨酸SAM膜电极上于不同pH值溶液中的电化学行为。循环伏安结果表明，在pH大于高半胱氨酸等电点的溶液中，[Fe(CN)6]^3-/4-在膜电极上的循环伏安曲线峰电流明显降低，峰分离差增大，说明随pH值的增加，[Fe(CN)6]^3-/4-离子对在SAM膜电极上的可逆性变差；交流阻抗图谱显示，由于SAM膜电极表面带负电荷时，[Fe(CN)6]^3-/4-难以靠近电极表面，使其与电极表面的电子交换反应变得困难，在SAM膜电极上的电化学反应电阻Rct明显增加，并且随电解质溶液的pH增加而增加。     

电子传输过程对硫醇自组装单层膜结构的影响

应用交流阻抗技术及循环伏安技术研究了十八硫醇修饰的金电极在Fe(CN)63-/4-溶液中的电化学行为,提出电化学氧化还原过程中的电子传输可以诱导十八烷基硫醇自组装单分子层膜结构的一定重组,使其变得更加均一有序.     

含咪唑烷基硫醇自组装膜界面铜离子配位研究

合成了6-(咪唑-2-基)-1-己硫醇(IHT),在金电极表面形成纯的自组装膜及其与1-己硫醇(HT)的混合自组装膜,并将这些自组装膜在溶液中与铜离子进行界面配位.应用电化学循环伏安法和交流阻抗谱法探讨了各种自组装膜修饰电极界面配位铜离子的电化学行为.实验结果表明,IHT与HT以1∶4比例进行界面组装得到的混合自组装单分子层最致密,自组装膜的铜离子界面配位浓度最高达到2.3×10-11mol/cm2.界面形成的IHT-Cu2+配合物在不同的pH值溶液中测量结果表明该配合物在pH 6.4时是可以稳定存在的.     

12硫醇修饰金电极K_3Fe(CN)_6/K_4Fe(CN)_6体系的电化学参数

采用自组装(SA)技术制备了正十二硫醇的SA 单分子层膜.应用电化学交流阻抗及循环伏安技术研究了12 硫醇SA 单分子层膜在K3Fe(CN)6/K4Fe(CN)6 溶液中的电化学行为.测得了表观电子传递系数α+ β≠1,电子隧穿系数为(0.83～1.11)/CH2.     

噻吩羧酸在金表面的自组装膜及其电化学性质

研究了具有平面环状共轭体系的硫杂环化合物噻吩羧酸在金表面的自组装单分子膜及其修饰金电极的电化学行为．以Fe(CN)6^4-/3-为“探针”离子，用循环伏安法对自组装膜的形成、电极界面电容及其组装机理进行了研究．结果是噻吩羧酸在Au上的覆盖度约为95％，金电极的界面微分充电电容由修饰前的0．294μF／cm^2下降到0．167μF／cm^2，由此可见噻吩羧酸在金表面形成了致密的单分子膜．     

对羟基苯硫酚自组装膜修饰金电极的制备及电化学表征

在金电极表面制备了对羟基苯硫酚(4-HTP)自组装单分子膜,构建了一种羟基化金电极表面.在优化实验条件下,利用交流阻抗技术对4-HTP自组装单分子膜电极(4-HTP SAM/Au)进行了原位表征,采用Randles等效电路对阻抗复平面图进行模拟,确定该电极体系的等效电路以及电化学参数,通过电荷传递电阻Rct与组装时间的关系,给出了4-HTP SAM在金电极表面的组装动力学曲线.结果表明,电子传递电阻(Rct)随自组装时间的延长而迅速减小,证明4-HTP SAM是一种导电膜,当自组装时间达到120 min后,Rct不再变化,4-HTP SAM达到组装平衡状态.研究结果对SAMs的制备具有一定指导意义,在生物传感器的研究中具有应用前景.     

DNAzyme在金电极上自组装电化学生物传感器的制备

利用巯基与金表面Au-S键的自组装技术,可以将巯基修饰的DNAzyme固定在金电极表面形成电化学生物传感器,并以含有[Fe(CN)6]3-/4-的磷酸缓冲液(PBS)作为电化学检测底液,利用循环伏安法初步研究该修饰电极的电化学行为和修饰过程的电化学表征.DNAzymes自组装膜的存在明显抑制了二茂铁与[Fe(CN)6]3-/4-之间的电子转移.结果表明,基于巯基修饰的DNAzyme在金电极表面能够发生自组装作用,在金电极表面形成较为稳固的自组装DNAzyme膜.     

Au/CaM自组装膜方波伏安法表征

采用方波伏安法,在包含1 mmol/L[Fe(CN)6]3-/[Fe(CN)6]4-的0.15 mol/L的NaCl溶液中,对Au/CaM膜的电化学行为进行了初步表征。由方波伏安电流响应图可知:CaM可以在Au基底自组装成膜,[Fe(CN)6]3-/[Fe(CN)6]4-在Au/CaM膜电极上发生的是电化学不可逆反应过程。     

超氧化物歧化酶模型化合物在金电极上的分子自组装

采用3-巯基丙酸在金电极上自组装得到自组装单分子层(SAM),再利用DCC作酰胺键偶合剂,将超氧化物歧化酶(SOD)模型化合物Fe(IDB)Cl3(简称Fe-MSOD,IDB为N,N-二(2′-苯并咪唑甲基)亚胺)共价键合到自组装在金电极表面的3-巯基丙酸单分子层上,构筑了一种超氧化物歧化酶模型化合物分子组装体系膜修饰电极(Fe-MSOD/3-MPA/Au).采用电化学循环伏安法、交流阻抗法对该修饰电极进行了表征.初步探讨了此修饰电极的电化学氧化还原性质.     

超氧化物歧化酶模型化合物在金电极上的分子A组装

采用3-巯基丙酸在金电极上自组装得到自组装单分子层(SAM)，再利用DCC作酰胺键偶合剂，将超氧化物歧化酶(SOD)模型化合物Fe(IDB)CI3(简称Fe-MSOD，IDB为N，N-二(2’-苯并咪唑甲基)亚胺)共价键合到自组装在金电极表面的3-巯基丙酸单分子层上，构筑了一种超氧化物歧化酶模型化合物分子组装体系膜修饰电极(Fe-MSOD／3-MPA／Au)．采用电化学循环伏安法、交流阻抗法对该修饰电极进行了表征．初步探讨了此修饰电极的电化学氧化还原性质．     

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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