硫氰酸钾/硫脲复合物对45碳钢的缓蚀性能评价

本研究借助静态腐蚀失重法确定了硫氰酸钾/硫脲缓蚀剂的最佳配方,并分别研究了该配方在5%硫酸、5%硝酸及5%盐酸中对45碳钢的缓蚀性能。结果表明:在5%硫酸溶液中,使用硫氰酸钾:硫脲为7:3的质量比配方,缓蚀剂为0.2%时对45碳钢的缓蚀达到最大,缓蚀率为82.3%;在5%硝酸溶液中,使用硫氰酸钾:硫脲为4:6的质量比配方,缓蚀剂的加入量为0.1%时对45碳钢的缓蚀率可达到99%以上;在5%盐酸中,只需加入0.2%的复合缓蚀剂(硫氰酸钾:硫脲=4:6),对45碳钢的缓蚀率可以达到76%。Tafel极化曲线表明硫氰酸钾/硫脲复合物的加入可以明显地降低45碳钢在3种酸溶液中的腐蚀电流。     

海水介质中环境友好型紫铜缓蚀剂的缓蚀性研究(英文)

采用失重法、极化曲线、电镜扫描和XPS能谱分析等方法对苯并三氮唑(BTA)及其复合缓蚀剂对海水中紫铜的缓蚀性能及缓蚀机理进行了研究。实验结果表明:单独使用BTA浓度达到150mg·L-1时,缓蚀率大于90%;BTA与柠檬酸钠复配后,缓蚀率有了很大提高,当BTA浓度为2mg·L-1,柠檬酸钠浓度为20mg·L-1时,缓蚀率达到96.0%,腐蚀速率为0.01014mm/a,缓蚀剂成本大大降低。极化曲线试验结果表明,BTA缓蚀剂在海水中为阴极型缓蚀剂,BTA与柠檬酸钠复合缓蚀剂为混合型缓蚀剂。对添加了缓蚀剂的海水中的紫铜表面进行的扫描电镜测试及XPS能谱分析的实验结果表明:添加了BTA和柠檬酸钠缓蚀剂的紫铜表面光滑,基本没有腐蚀;且在试片表面形成了缓蚀剂各组分均参与成膜的非水溶性保护层,有效的抑制了紫铜在海水中的溶解腐蚀。     

糠醛对紫铜的缓蚀与钝化作用研究

利用失重法及电化学极化曲线测量法，研究了糠醛在盐酸介质中对紫铜的缓蚀和钝化作用．结果表明：它对紫铜有较好的缓蚀和钝化性能     

硝酸钠与十二烷基苯磺酸钠在二氧化氯介质中对铝合金的协同缓蚀作用研究

为了探讨二氧化氯(ClO2)介质中金属的腐蚀问题,采用静态失重法、动电位极化曲线法和扫描电镜法研究了硝酸钠和十二烷基苯磺酸钠(DBSAS)在100mg/L二氧化氯介质中对铝合金的缓蚀协同效应。结果表明,硝酸钠对铝合金的缓蚀作用较差,最大缓蚀率仅为55.58%;DBSAS对铝合金有中等程度的缓蚀作用,缓蚀效率随其浓度的增加而增大,最大缓蚀率可达89.33%;硝酸钠和DBSAS复配后对铝合金产生明显的缓蚀协同效应,当硝酸钠和DBSAS复配的质量之比为3∶7时,最大缓蚀率可达96.28%。     

海水介质中环境友好型紫铜缓蚀剂的缓蚀性研究

采用失重法、极化曲线、电镜扫描和XPS能谱分析等方法对苯并三氮唑（BTA）及其复合缓蚀剂对海水中紫铜的缓蚀性能及缓蚀机理进行了研究。实验结果表明：单独使用BTA浓度达到150mg·L^-1时，缓蚀率大于90％；BTA与柠檬酸钠复配后，缓蚀率有了很大提高，当BTA浓度为2mg·L^-1，柠檬酸钠浓度为20mg·L^-1时，缓蚀率达到96．0％，腐蚀速率为0．01014mm／a，缓蚀剂成本大大降低。极化曲线试验结果表明，PGA缓蚀剂在海水中为阴极型缓蚀剂，BTA与柠檬酸钠复合缓蚀剂为混合型缓蚀剂。对添加了缓蚀剂的海水中的紫铜表面进行的扫描电镜测试及XPS能谱分析的实验结果表明：添加了BTA和柠檬酸钠缓蚀剂的紫铜表面光滑，基本没有腐蚀；且在试片表面形成了缓蚀剂各组分均参与成膜的非水溶性保护层，有效的抑制了紫铜在海水中的溶解腐蚀。     

Mannich碱缓蚀剂MH使用条件的优化研究

本文介绍了以苯乙酮、甲醛、苯胺为原料,合成Mannich碱缓蚀剂MH的方法,采用正交实验法考察了缓蚀剂浓度、腐蚀体系盐酸浓度、反应温度在盐酸介质中对N80挂片腐蚀速率的影响。结果表明:在盐酸介质中,当缓蚀剂浓度为0.5%,腐蚀体系盐酸浓度为10%,反应温度为40℃时,腐蚀速率最小,缓蚀剂缓蚀效果最好。     

氨基酸对A3钢的缓蚀作用及机理研究

考察了由豆类水解所得复合氨基酸对Ａ３钢的缓蚀作用。实验表明：在常温下盐酸介质中,当缓蚀剂＜１．０％时,抑制系数为ｌｇｒ＝２．４１＋０．４６ｌｇＣ主要表现为抑制阴极过程,呈现负催化效应。当添加量＞１．０％,腐蚀电位开始正移。体系升温后,缓蚀作用主要表现为阻止阳极溶解。     

高效含氮有机缓蚀剂BIEA及其复配剂的研究

合成了一种含氮有机化合物BIEA，采用失重法和电化学方法，测定了其与丙炔醇复配时在盐酸溶液中对45#钢的缓蚀效果。结果表明：BIEA与丙炔醇有很好的协同作用。BIEA与丙炔醇的复配体可同时抑制45#钢在盐酸中腐蚀的阴极过程与阳极过程，是混合型缓蚀剂。     

硫酸介质中四唑类化合物对紫铜的缓蚀作用

采用动电位极化曲线和电化学阻抗谱(EIS)技术,研究5-(4-羟苯基)-1,2,3,4-四唑(4-HPTT)和5-(4-氨苯基)-1,2,3,4-四唑(4-APTT)在暴露于空气的0.5 mol/L H2SO4介质中对紫铜的缓蚀作用。结果表明:在0.5 mol/LH2SO4溶液中,4-HPTT和4-APTT对紫铜的缓蚀效率随浓度的增加而增大,当4-HPTT和4-APTT浓度为0.25 mmol/L时,缓蚀效率分别达到99.3%和97.6%;4-HPTT为阴极型缓蚀剂,而4-APTT为混合型缓蚀剂;加入4-HPTT和4-APTT后紫铜的腐蚀控制步骤由活化和扩散的混合控制过程改变为电荷转移过程;4-HPTT和4-APTT在紫铜/溶液界面的吸附遵循Langmuir吸附等温式。     

双咪唑啉季铵盐缓蚀剂的合成及性能研究

将月桂酸、二乙烯三胺、碳酸二甲酯等作为原料合成一种双子咪唑啉季铵盐类化合物,并在3.5%Na Cl溶液中通过静态失重法测定该缓蚀剂对马口铁片的缓蚀能力,考察了缓蚀剂浓度、温度等因素对其缓蚀性能的影响。通过Tafel曲线和交流阻抗的测定,对其缓蚀性能进行进一步考察。结果表明双子咪唑啉缓蚀剂在3.5%NaCl溶液的腐蚀环境中对马口铁片具有好的缓蚀效果。当温度T为30℃,缓蚀剂浓度为50 mg/L时,其缓蚀率最大可到91.25%。Tafel曲线表明缓蚀剂浓度增加,其腐蚀电位会向正电位方向移动,且自腐蚀电流密度也在很大程度上随之降低,缓蚀率在增加。从交流阻抗谱的阻值半径可知当缓蚀剂浓度为50 mg/L时得到的阻抗谱半径最大,说明在这一浓度下,腐蚀速率最小,缓蚀效果最优。     

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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