季铵化聚乙烯亚胺的抗菌性能研究

采用叔胺化反应与季铵化反应两步高分子反应过程,制备了季铵化的聚乙烯亚胺(QPEI);以大肠杆菌(E.coli)为致病菌体,重点研究了高分子季铵盐QPEI的抗菌活性;采用平板活菌记数法考察了季铵化度及pH值等因素对其抗菌性能的影响规律;并采用β-半乳糖苷酶活性测定法,研究了QPEI的抗菌机理.研究结果表明,QPEI具有很强的抗菌能力,对浓度为109CFU/mL的菌悬液,在药剂量为15mg/L、接触时间为4min的条件下,杀菌率可达100%;QPEI的季铵化度对其抗菌性能影响很大,季铵化度越高,抗菌性能越好;在一定的pH值范围内,pH值越高,抗菌性能越好.β-半乳糖苷酶活性测定结果表明,QPEI的抗菌机理是基于杀菌过程,而不只是抑菌作用.     

曲唑酮的两步法制备及对碳钢的缓蚀机理

以3-氯苯胺、N-氯丙基二乙醇胺和吡啶三唑酮为原料，两步法制备出曲唑酮（TZD）.通过动态失重、极化曲线与电化学阻抗谱研究了TZD在0.5 mol/L盐酸溶液中对20#钢的缓蚀性能；借助扫描电子显微镜、原子力显微镜、衰减全反射红外光谱与吸附活化参数分析研究了TZD在碳钢表面的作用机理.结果表明，TZD可显著降低碳钢在盐酸溶液中的腐蚀速率，缓蚀率随TZD添加浓度的增加而增大，随温度升高而降低；298 K下，添加6 mmol/L TZD时，缓蚀率达95.8%；TZD可自发吸附组装于碳钢表面，同时抑制腐蚀反应的阴、阳极过程，显著增加界面极化阻抗；吸附为放热过程，符合Langmuir等温式.理论计算结果显示，TZD倾向以平行取向组装于碳钢表面.     

甲基丙烯酸二甲氨基乙酯类离子液体 对Q235钢的缓蚀性能

以甲基丙烯酸二甲氨基乙酯为母体、 对氯甲基苯乙烯为季铵化试剂, 合成了一种具有疏水结构的甲基丙烯酸二甲氨基乙酯型离子液体(DEMA). 通过失重实验、 电化学分析、 原子力显微镜(AFM)、 接触角测试和量子化学计算等研究了DEMA在1 mol/L盐酸中对Q235钢的缓蚀性能, 并揭示了其在Q235钢表面的吸附行为和吸附机理. 失重实验结果表明, DEMA在盐酸中对Q235钢具有优异的缓蚀效果, 且在较高温度(60 ℃)下也能保持高效吸附; 电化学实验结果与失重测试结果一致; 接触角测试结果表明, DEMA可明显增强Q235钢表面的疏水性; 分析热力学参数可知, DEMA在Q235钢表面的吸附为自发、 放热过程, 符合Langmuir等温式, 且以化学吸附为主; 量子化学计算结果证实DEMA的结构中包含大量吸附活性位点.     

季铵化聚乙烯亚胺的制备

以环氧丙烷为叔胺化试剂,氯化苄为季铵化试剂通过聚乙烯亚胺(PEI)的叔胺化与季铵化反应制备了季铵化的聚乙烯亚胺(QPEI),其结构经IR表征。考察了反应条件对合成QPEI的影响。研究结果表明,使用环氧丙烷,可绿色化地实现PEI链中的伯胺基和仲胺基的叔胺化得到叔胺化的聚乙烯亚胺(TPEI);以氯化苄为季铵化试剂,于50℃反应30 h可使TPEI链中90%以上的叔胺基实现季铵化,从而使PEI链中的总N原子数实现50%以上的季铵化。     

两种席夫碱缓蚀剂对碳钢材料的缓蚀性能探究

采用了电化学方法研究了2种席夫碱缓蚀剂水杨醛基邻苯甲酸亚胺(SB-I)和N,N’-二水杨醛基-1,2-邻苯二亚胺(SB-II)在1 mol/L盐酸溶液中对20#碳钢的缓蚀性能。通过极化曲线和交流阻抗谱研究该席夫碱对碳钢的缓蚀效果表明:席夫碱对碳钢材料具有良好的缓蚀作用,其最大缓蚀率可达到83%。研究了席夫碱在碳钢表面的吸附模式,结果表明,席夫碱在碳钢表面上的吸附吉布斯自由能在-30 kJ/mol之间,表现为混合型缓蚀剂,即通过化学吸附和物理吸附之间的一种混合吸附在碳钢工作电极的表面,通过抑制、阻止延缓金属的电化学过程而起到缓蚀的作用。另外,实验还发现,SB-I比SB-II具有更好的缓蚀性能,该实验结果与理论计算结果相符合。     

阳离子功能接枝微粒QPDMAEMA/SiO_2的制备及其对阿魏酸吸附特性的研究

使含有氨基的改性硅胶微粒表面的氨基与溶液中的过硫酸盐构成氧化-还原引发体系,实施了甲基丙烯酸二甲基氨基乙酯(DMAEMA)在硅胶微粒表面的引发接枝聚合,制得接枝微粒PDMAEMA/SiO2;又以氯乙胺为试剂,使接枝的大分子PDMAEMA的叔胺基团发生季铵化反应,实现了接枝微粒PDMAEMA/SiO2的季铵化(Quaternization)转变,制得了阳离子性功能接枝微粒QPDMAEMA/SiO2。采用红外光谱(FTIR)、扫描电子显微镜(SEM)及Zeta电位测定等多种手段对两种微粒进行了表征。主要研究了温度对接枝聚合和季铵化转变反应的影响,优化了反应条件。还考察了功能接枝微粒QPDMAEMA/SiO2对阿魏酸的子吸附性能。研究结果表明,采用-NH2//S2O82-表面引发体系,可有效地实现DMAEMA的接枝聚合,适宜的反应温度为35℃;氯乙胺与接枝微粒叔胺基团之间的季铵化反应可顺利进行,适宜的反应温度为60℃,叔胺基团的季铵化度可达82%。凭借主-客体之间的强静电相互作用并协同以阳离子-π相互作用,功能接枝微粒QPDMAEMA/SiO2对阿魏酸可产生很强的吸附作用,在中性条件下,吸附容量高达187mg/g。     

新型不对称双季铵盐缓蚀剂在HCl中对Q235钢的缓蚀行为

采用静态失重法、极化曲线法和交流阻抗法研究了自制的含咪唑啉环不对称双季铵盐缓蚀剂(DBA)在1 mol•L^－1 HCl介质中对Q235钢的缓蚀性能, 并探讨了其在Q235钢表面的吸附行为. 结果表明, 缓蚀效率随DBA浓度增加而增大, 在25～55 ℃的实验温度范围内, 浓度为2.89×10^－4 mol•L^－1时, 缓蚀效率均在90%以上, 且缓蚀效率随温度升高而增大. 极化曲线测试显示DBA是一种阴极抑制为主的混合型缓蚀剂. 缓蚀剂在Q235钢表面的吸附过程为吸热过程, 其在Q235钢表面的吸附遵循Langmuir等温式, 属于化学吸附. 最后采用量子化学方法对DBA的缓蚀机理做了进一步分析.     

2种癸二酸咪唑啉季铵盐的合成及缓蚀性能评价

合成了2种癸二酸咪唑啉季铵盐癸二酸-水杨酸咪唑啉季铵盐(SSAI)和癸二酸咪唑啉季铵盐(SAI),并采用失重法和电化学方法研究了这2种咪唑啉季铵盐对N80钢在1 mol/L HCl溶液中的缓蚀性能和吸附行为。 结果表明,在1 mol/L HCl溶液中这2种化合物对N80钢均有较好的缓蚀作用,缓蚀效率大小顺序为SSAI＞SAI。 SSAI和SAI均为混合偏阳极型缓蚀剂。 2种化合物在N80钢表面的吸附服从Langmuir吸附等温式,属于化学吸附。     

含硫杂环结构氨基醇化合物的合成及缓蚀性能研究

以2-噻吩甲胺和乙二醇二缩水甘油醚为原料，在较温和的条件下，合成了一种结构新颖的含硫杂化结构的氨基醇化合物(DS)。分别用电化学法和失重法研究了DS在0.5 mol/L H₂SO₄溶液中对20#碳钢的腐蚀抑制作用。动电位极化曲线表明化合物DS在0.5 mol/L H₂SO₄溶液中以抑制阴极析氢反应为主，当DS浓度为50 mg/L时，对碳钢的缓蚀效率达到93%,具有用量小、缓释效率高的特点。吸附等温线研究表明：DS分子在碳钢表面的吸附行为符合Langumir单分子层吸附模型，既存在物理吸附，也存在化学吸附。化合物DS合成步骤简单、缓蚀效率高，在碳钢设备除锈、除垢等领域具有良好的应用前景。     

肉桂醛壳聚糖席夫碱对N80钢的缓蚀行为评价

以肉桂醛改性壳聚糖制备了肉桂醛壳聚糖席夫碱(CACS),利用红外光谱、热重实验对其结构表征。利用失重实验、电化学极化曲线评价了其在1 mol/L氨基磺酸中对N80钢的缓蚀性能。结果表明在1 mol/L氨基磺酸中CACS能有效的抑制酸液对N80钢的腐蚀,当其浓度为1000 mg/L时,缓蚀率高达98.09%,属于混合抑制型缓蚀剂。吸附模型分析可知CACS在N80表面的吸附与Langmuir吸附模型相符,存在化学与物理两种吸附形式,且CACS加入后提高了腐蚀过程的活化能,减慢了腐蚀反应速率,抑制了N80钢的腐蚀。     

Influence of inhibitor structure and metal/solution interface on the corrosion resistance of the protected metal

Seven systems of more than 60 compounds with possible inhibiting properties are investigated. Several methods are used: electrochemical, gravimetric, XPS, and SEM analyses. The inhibition efficiency Z is related to the chemical structure of inhibitors (sequences of compounds with regard to Z are found), their electronic structure, the surface area of the inhibiting molecule, and the structure and composition of the metal/solution interface (impedance, adsorption equilibrium parameters, etc.). The most efficient of the investigated inhibitors have Z = 94–99%. Conclusions are drawn which allow identification of compounds with prognosticated inhibiting action. Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 11, pp. 1352–1364. Based on the report delivered at the 8th International Frumkin Symposium “Kinetics of the Electrode Processes,” October 18–22, 2005, Moscow. The text was submitted by the authors in English.     

苯并三唑和六亚甲基四胺的缓蚀作用研究

在含氯化钠和盐酸的流动介质中研究铁的腐蚀行为以及苯并三唑和六亚甲基四胺对阳、阴极过程的影响。这两种含氮有机物均对铁上的析氢反应产生强烈的阻化作用,归因于阻塞效应和静电效应。发现有机物浓度的对数与缓蚀效率的对数成线性关性,它们的吸附遵循修正的Freundlich等温线。     

Synthesis and Effect of Some 5-Alkyl-1,3,4-Triazole-2-Thione Derivatives on Corrosion Behavior of Molybdenum Electrode in Hydrochloric Acid

A novel series of self-assembled surfactants derived from 5-alkyl-1,3,4-triazole-2-thione have been synthesized. The purity of surfactants synthesized was checked by rutinary methodologies (FTIR spectroscopy, ¹H-NMR, MS and elemental analysis). Their surface active properties at equilibrium in water at 25°C were determined. Also, the inhibitive effect of these compounds, in the case of molybdenum in acid medium, was investigated thoursough galvanostatic and galvanodynamic techniques. Galvanodynamic polarization data indicates that these surfactants act as very good inhibitors of molybdenum in hydrochloric acid both for cathode and anode. Galvanostatic measurement has the same trend of inhibitive effect as that of the galvanodynamic polarization data, which indicate the formation of a protective layer on the metal surface by the adsorption of surfactants molecules.     

一种氨烷基膦酸型水处理剂的合成及缓蚀阻垢性能的研究

介绍了一种氨烷基膦酸型水处理剂二甲基氨基甲叉二膦酸(DMAMDP)的合成方法,并进行了缓蚀阻垢性能的研究。结果表明,DMAMDP在阻碳酸钙、硫酸钙、磷酸钙和稳定锌等方面,以及缓蚀性能均优于常用有机膦酸水处理剂HEDP和ATMP。     

Experimental and theoretical studies on the inhibition potentials of some derivatives of cyclopenta‐1,3‐diene for the corrosion of mild steel in HCl solutions

The inhibition of the corrosion of mild steel in HCl by some cyclopentadiene‐1,3‐diene derivatives, namely, 1‐(thiophen‐2‐yl)ethanone (2APT), 1‐(1H‐pyrrol‐2‐yl)ethanone (2AP), and (E)‐2‐(1‐hydrazonoethyl)‐1H‐pyrrole (2APH)), was studied experimentally using weight loss and hydrogen gas evolution measurements. The theoretical aspect was studied using the density functional theory and quantitative structure activity relation (QSAR) methods. The results obtained indicated that the studied compounds are good inhibitors for the corrosion of mild steel in HCl. The adsorption of the inhibitor on mild steel surface was found to be spontaneous, exothermic, and obeyed the Langmuir adsorption isotherm model. A good correlation was found between experimental inhibition efficiencies and some calculated quantum chemical parameters and also with the theoretical inhibition efficiencies obtained from QSAR modeling. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Synthesis, Crystal Structure and Inhibition Corrosion Effect of Bis-（1,1＇-benzotriazoly）-a,w-decoyldiamide

The title compound bis-(1,1’-benzotriazoly)-α,ω-decoyldiamide was synthesized by the reaction of benzotriazole with sebacoyl dichloride, and its structure was characterized by IR, 1H NMR and single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P with a = 5.5290(11), b = 7.9410(16), c = 12.401(3), α = 72.19, β = 78.87(3), γ = 82.82(3)°, V = 507.36(20) 3, C22H24N6O2, Mr = 404.47, Dc = 1.324 g/cm3, Z = 1, μ = 0.089 mm-1, F(000) = 214, the final R = 0.0481 and wR = 0.1342 for 1347 observed reflections with I > 2σ(I). X-ray analysis revealed that the benzotriazole ring and carbonyl group were essentially planar. Potentiodynamic polarization study showed that inhibitor inhibited the anodic corrosion reactions, and it was an anodic type inhibitor.     

Corrosion inhibition of zinc-plated steel in 0.5, 1 and 1.5 M sulphuric acid by poly(ethylene glycol)

The effect of poly(ethylene glycol) (PEG) 4000 on the corrosion of zinc-plated steel in H₂SO₄ has been investigated over a wide range of conditions. It was found that the corrosion rate depends upon exposure time. The rate of corrosion goes down rapidly to reach a low value, which is an almost constant value within 5 hr under most conditions. This trend was also found by Growock and Lopp for the inhibition of steel corrosion in HCl with 3-phenyl-2-propyl-1-ol. Other workers have linked this slow fall-off in the corrosion rate to film formation. The corrosion rate was found to decrease slowly with increasing PEG concentration, and to increase slowly with acid concentration for all conditions. The effect of temperature on corrosion rate was found to be similar to that of acid concentration. The corrosion rate decreased exponentially with poly(ethylene glycol) concentration. The percentage inhibition reached a value of 48.93 for a PEG concentration of 4 ppm: to double this, the concentration had to be increased to 40,000 ppm. Sulphuric acid titration against sodium hydroxide showed no change in acid concentration during the corrosion protection process, thus supporting the film protection theory     

Inhibitive action of ethanol extracts from Nauclea latifolia on the corrosion of mild steel in H2SO4 solutions and their adsorption characteristics

The inhibitive action of ethanol extracts from leaves (LV), bark (BK) and roots (RT) of Nauclea latifolia on mild steel corrosion in H₂SO₄ solutions at 30–60 °C was studied using weight loss and gasometric techniques. The extracts were found to inhibit the corrosion of mild steel in H₂SO₄ solutions and the inhibition efficiencies of the extracts follow the trend: RT > LV > BK. The inhibition efficiency increased with the extracts concentration but decreased with temperature rise. Physical adsorption of the phytochemical components of the plant on the metal surface is proposed as the mechanism of inhibition. The adsorption characteristics of the inhibitor were approximated by the thermodynamic-kinetic model of El-Awady et al.     

Influence of Molecular Weight on Mild Steel Corrosion Inhibition Effect by Polyvinyl Alcohol in Hydrochloric Acid Solution

The corrosion inhibition of mild steel in hydrochloric acid solution in the presence of three different molecular weights of polyvinyl alcohol (PVA) designated as PVA-I, PVA-II, and PVA-III corresponding to 14,000, 72,000, and 125,000 g mol^?1, respectively, was investigated using electrochemical impedance spectroscopy, linear polarization resistance (LPR), and potentiodynamic polarization techniques at 25°C. It was found that PVA of different molecular weights inhibited the corrosion of mild steel in the acid environment. Inhibition efficiency (η%) increases with increase in concentration of the polymers. LPR measurements clearly show that inhibition efficiency increases with increasing molecular weight in the order PVA-III > PVA-II > PVA-I. Polarization curves indicate that PVA functions as a mixed inhibitor affecting both the anodic metal dissolution and cathodic hydrogen evolution partial reactions of the corrosion process. The experimental data obtained fitted well into Langmuir adsorption isotherm model. Physical adsorption mechanism is proposed from the thermodynamic (free energy of adsorption) parameters obtained.     

SERS技术对聚天冬氨酸缓蚀性能的研究

SERS技术对聚天冬氨酸缓蚀性能的研究;缓蚀作用;表面增强拉曼散射