有膜法电化学合成丁二酸的研究

研究了有膜法电化学合成丁二酸的电解过程,探讨了硫酸浓度、电流密度、初始马来酸浓度、温度对转化率、电流效率、电能的影响,获得适宜的阴极电解条件为硫酸浓度0．6—0．9kmol／m^3,电流密度0．15A／cm^2,马来酸浓度1．0-1．5kmol／m^3,温度50-55℃。     

丁二酸的电解合成

本文应用有机电解合成的方法对丁二酸的合成作了一些探讨,获得了满意的效果.实验摸索了电流效率、电耗、通电时间对合成丁二酸的影响,找了了影响反应的因素.     

离子交换膜法合成二氯联苯胺盐酸盐

本文采用离子交换膜法合成3,3’-二氯联苯胺盐酸盐。研究了电解温度、阳极电解液浓度和用回收电解液对反应电流效率和产率的影响。结果表明：反应条件为t=80℃，阳极电解液浓度为30%（质量分数），阴极电解液浓度为10%（质量分数）时，电流效率最高，可达到93%，收率达到90%；还原反应所用的电解液，经简单处理后均可以回收使用，几乎不影响相应的实验结果。     

纳米TiO2膜阴极电催化合成丁二酸的研究

采用电化学合成前驱体直接水解法制备纳米TiO2膜修饰电极,通过循环伏安法研究了纳米TiO2膜电极的电化学行为,并使用纳米TiO2膜电极作为阴极在三室离子膜电解槽中电解还原顺丁烯二酸 (cis-butenedioic acid)合成丁二酸(butanedioic acid), 探索了影响电合成丁二酸电流效率的主要因素. 结果表明,纳米TiO2膜电极具有异相电催化行为,纳米膜中的TiⅣ/TiⅢ氧化还原电对作为媒质间接电还原顺丁烯二酸为丁二酸, 电合成丁二酸的一次结晶产品纯度高、电解副反应少、收率和电流效率高,控制阴极电位-0.6 V (vs. SCE), 电流密度6 A/dm2,电解液为1.0 mol/L顺丁烯二酸 1.0 mol/L硫酸溶液, 电流效率达到88%以上.     

Pb-Zn多孔电极电还原顺丁烯二酸

在甲磺酸镀液中电沉积Pb-Zn镀层,采用体积分数为10%的H2SO4腐蚀镀层使锌溶出,得到Pb-Zn多孔电极.通过线性扫描伏安法和恒电位阶跃实验分析多孔Pb-Zn电极的电化学性质,表明电极对顺丁烯二酸电还原合成丁二酸具有较好的电催化活性.研究无膜电合成丁二酸,探讨硫酸浓度、电流密度、初始顺丁烯二酸浓度、温度对电流效率的影响,得到合适的阴极电解条件,即在硫酸浓度为1.0mol·L-1,初始顺丁烯二酸浓度为1.0～1.5mol·L-1,电流密度为100mA·cm-2,反应温度为50～60℃时,电流效率超过88%.     

电解致酸脱保护DNA在片合成研究

提出了以电解致酸脱保护法为特征的是阻DNA在片合成新方法，在2．0V电解电位下电解水，释放氢离子并富集于阳极极板队近，导致局部酸度增强，使核酸单体分子发生脱保护反应，测定了该合成方法的合成产率与电解时间，支持电解质浓度，水浓度等条件的关系，结果表明，电解时间越长，脱保护效率越高，两者基本呈线性关系；支持电解质浓度与水浓度等条件对脱保护效率基本无影响。     

单室无隔膜电解槽中恒电流电解合成丁二酸的研究

旨在寻找和研制电还原顺丁烯二酸制备丁二酸中高活性、高选择性的电极材料,采用自行研制的不锈钢(Stainlesssteel,SS)载表面合金电催化材料(Surface alloy/SS)作为工作电极,利用CV研究了其在常温常压、不同电流密度和支持电解质等条件下顺丁烯二酸电合成丁二酸中的性能,通过离子色谱电导检测等技术对电合成产物进行检测分析.结果表明:Surface alloy/SS电极对顺丁烯二酸的加氢还原表现出很高的电催化活性;对产物丁二酸的选择性高;优化的电解条件为:电流密度27.68 mA·cm-2,0.1 mol·L-1硫酸作为支持电解质.     

准液膜法处理含铬废水影响因素的实验研究

本文利用自制的不同浓度的酸性重铬酸钠溶液为合成废水,对准液膜法处理含铬废水影响因素进行了实验研究,发现碱液下落状态和酸度、提取次数是影响准液膜法处理含铬废水的主要因素。     

N—甲基-2-吡咯烷酮的电解合成

以丁二酸和甲胺水溶液为原料,先合成N—甲基丁二酰亚胺,再经电解还原得N—甲基—2—吡咯烷酮。经分离提纯,含量达99.5%以上,可满足液晶技术的使用要求。     

电合成丁二酸中阳极材料的选用

本文分析比较了电合成丁二酸发展过程中使用不同的阳极时的电耗、寿命、电流密度、收率以及对丁二酸产品质量的影响,指出了用于电合成丁二酸的阳极材料的今后发展方向。     

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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