共查询到20条相似文献,搜索用时 15 毫秒
1.
R. A. Prabhu T. V. Venkatesha A. V. Shanbhag 《Journal of the Iranian Chemical Society》2009,6(2):353-363
The inhibition action of carmine and fast green dyes on corrosion of mild steel in 0.5 M HCl was investigated using mass loss, polarization and electrochemical impedance (EIS) methods at 300 K. The inhibition efficiency was found to increase with increasing concentration of the inhibitors. The inhibition efficiency of fast green (%η - 98) is higher than that of carmine (%η - 92) and found to be maximum in 1 × 10-3 M solution. The inhibitors act as mixed type with predominant cathodic effect. The inhibitors were adsorbed on the mild steel surface according to the Temkin adsorption isotherm. The surface morphology of the mild steel specimens was evaluated using SEM images. 相似文献
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嘧啶衍生物对钢在盐酸溶液中的缓蚀作用 总被引:1,自引:0,他引:1
采用失重法、动电位极化曲线、电化学阻抗谱(EIS)、量子化学计算研究了两种嘧啶衍生物(2-羟基嘧啶(HP)和2-巯基嘧啶(MP))在1.0-5.0 mol·L-1 HCl溶液中对冷轧钢(CRS)的缓蚀作用. 结果表明: HP和MP在1.0 mol·L-1 HCl溶液中对冷轧钢具有良好的缓蚀作用, 且在钢表面的吸附符合Langmuir吸附等温式. 缓蚀率随缓蚀剂浓度的增加而增大, 但随盐酸浓度的增加而减小.求出了相应的吸附热力学参数(吸附平衡常数(K),吸附自由能(ΔG0))和腐蚀动力学参数(表观活化能(Ea)、指前因子(A)、腐蚀速率常数(k)、动力学常数(B)), 并根据这些参数讨论了缓蚀作用机理. 动电位极化曲线表明, MP和HP均为混合抑制型缓蚀剂; EIS谱呈单一容抗弧,电荷转移电阻随缓蚀剂浓度的增加而增大. 两种嘧啶化合物的缓蚀率排序为MP>HP. 量子化学计算结果表明,MP比HP更具吸附活性,缓蚀性能的理论计算和实验结果相一致. 相似文献
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Ismail Kayagil Seref Demirayak 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2197-2207
In this study, 2-substituted 4-[3/4-(4-arylthiazole-2-yl)aminophenyl]thiazole derivatives and 2-[4-[2-substituted 4-methylthiazole-5-yl]thiazole-2-yl]amino-5-arylidenethiazoline-4-one derivatives have been synthesized. The cytotoxic and/or growth inhibitory effects of the 16 selected compounds were evaluated in vitro against approximately 66 human tumor cell lines derived from nine neoplastic diseases. Some of the compounds were found to act as anticancer agents. 相似文献
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Carlos Cevallos-Morillo Pablo Cisneros-Prez Roxana Llive Marvin Ricaurte Carlos Reinoso Miguel Angel Meneses Maria del Cisne Guamn Alex Palma-Cando 《Molecules (Basel, Switzerland)》2021,26(24)
Croton lechleri, commonly known as Dragon’s blood, is a tree cultivated in the northwest Amazon rainforest of Ecuador and Peru. This tree produces a deep red latex which is composed of different natural products such as phenolic compounds, alkaloids, and others. The chemical structures of these natural products found in C. lechleri latex are promising corrosion inhibitors of admiralty brass (AB), due to the number of heteroatoms and π structures. In this work, three different extracts of C. lechleri latex were obtained, characterized phytochemically, and employed as novel green corrosion inhibitors of AB. The corrosion inhibition efficiency (IE%) was determined in an aqueous 0.5 M HCl solution by potentiodynamic polarization (Tafel plots) and electrochemical impedance spectroscopy, measuring current density and charge transfer resistance, respectively. In addition, surface characterization of AB was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy techniques. Chloroform alkaloid-rich extracts resulted in IE% of 57% at 50 ppm, attributed to the formation of a layer of organic compounds on the AB surface that hindered the dezincification process. The formulation of corrosion inhibitors from C. lechleri latex allows for the valorization of non-edible natural sources and the diversification of the offer of green corrosion inhibitors for the chemical treatment of heat exchangers. 相似文献
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The inhibition effect of three azole compounds, 2-aminobenzimidazole(ABM), 2-aminothiazole(AT) and 2-aminobenzothiazole(ABT), on the corrosion of mild steel in a 1 mol/L HCl solution was investigated by means of potentiodynamic polarization measurement, electrochemical impedance spectroscopy(EIS) and scanning electron mi-croscopy(SEM). The correlation between inhibition efficiency and molecular structure of inhibitor was theoretically studied via quantum chemical calculations. The results show that the inhibition efficiency(η) of the inhibitors follows the order of ηABT >ηAT >ηABM. Moreover, ABM, AT and ABT belong to mixed-type inhibitors. The adsorption of the inhibitors on the steel surface follows the Langmuir adsorption isotherm, with both physisorption and chemisorption. 相似文献
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《Journal of heterocyclic chemistry》2017,54(6):3395-3402
A series of novel thiazole acrylonitrile derivatives was designed and synthesized utilizing NC‐510 as a precursor. Their structures were characterized by NMR spectrometry, MS, and elemental analysis. The results of bioassay indicated that some of these title compounds exhibited 100% mortality at 50 mg/L against Aphis fabae . In particular, the compound 11c displayed the best activity: Its LC50 value achieved 1.45 mg/L, and its insecticidal potency is comparable with that of NC‐510. 相似文献
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Liu Yuting Liu Kai Yin Dawei Yang Lisha Dang Yang Yang Lan Zou Qian 《Russian Journal of Organic Chemistry》2019,55(4):554-558
Russian Journal of Organic Chemistry - Three novel dendritic phenothiazine derivatives consisting of a biphenyl core, phenothiazine branching units, and terminal 3,7-di-tert-butylphenothiazine... 相似文献
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Chang Bin GUO Zhe Feng CAI Zong Ru GUO Zhi Qiang FENG Feng Ming CHU Gui-Fang CHENG 《中国化学快报》2006,17(3):325-328
Selective cyclooxygenase-2 (COX-2) inhibitors exhibite advantages for inflammation and pain relief without the gastrointestinal damage and hematologic liabilities observed with traditional non-steroidal anti-inflammatory drugs (NSAIDs) which can inhibit b… 相似文献
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Zienab M. Nofal Elsyed A. Soliman Somaia S. Abd El‐Karim Magdy I. El‐Zahar Aladdin M. Srour Shalini Sethumadhavan Timothy J. Maher 《Journal of heterocyclic chemistry》2014,51(6):1797-1806
4‐(1H‐benzo[d]imidazol‐2‐yl)thiazol‐2‐amine and its 1‐methyl derivative ( 1 ) were reacted with different reagents such as acid anhydrides, malononitrile, chloroacetyl chloride, and aromatic aldehydes to produce the corresponding benzimidazole products 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , respectively. Also, 2‐chloro‐N‐(4‐(1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)thiazol‐2‐yl) acetamide ( 6 ) was reacted with diaminoethane, ortho‐substituted aniline, thioglycolic acid, thiosemicarbazide derivatives, secondary amines, and potassium isothiocyanate to afford the corresponding derivatives 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , respectively. The cytotoxic activity of some newly synthesized derivatives was studied against two different cell lines HepG2 and PC12. Compounds 9 and 15b showed promising anticancer activity against both types of the tested cancerous cell lines. 相似文献
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2‐Ethoxy carbonylcyclopentanone (1) has been brominated to yield 2‐bromo‐2‐ethoxy carbonylcyclopentanone (2) which on further reaction with substituted thiosemicarbazones, thiocarbohydrazones, thiocarbamides and carbamides has furnished 1 ‐ thia‐3,4‐diaza‐5,7‐dioxo‐2‐[(substituted benzylidine)‐amino]spiro[4.5]dec‐2‐ene (3a–e) , 1‐thia‐3,4‐diaza‐5,7‐dioxo‐2‐[(substituted benzylidine)‐hydrazino] spiro[4.5]dec‐2‐ene (4a–e) , 1‐thia‐3‐aza‐2‐(substituted imino)‐4,6‐dioxo‐spiro[4.4]nonane (5a–f) and 1‐oxa‐3‐aza‐2‐(substituted imino)‐4,6‐dioxo‐spiro[4.4]nonane (6a–g) respectively. The structures of the compounds have been elucidated on the basis of spectral analysis. 相似文献
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《结构化学》2016,(3)
Two novel naphthol derivatives(1 and 2) were synthesized and characterized via IR,~1H NMR,and HRMS.The structure of compound 2 was verified by single-crystal X-ray crystallography.It crystallizes in monoclinic,space group C2/c with a = 21.6725(9),b = 6.0127(3),c = 25.5405(14) ?,β = 94.716(5)o,V = 3316.9(3) ?~3,Z = 8,F(000) = 1384,D_c = 1.511 Mg/m~3,M_r = 377.22 and μ = 2.487 mm~(-1).In addition,their cholinesterase inhibitory activities in vitro toward Electrophorus electricus acetylcholinesterase(eel ACh E) and horse serum butyrylcholinesterase(eq BCh E) were further determined.The results showed that compound 1 as a new acetylcholinesterase(ACh E) inhibitor displayed higher ACh E inhibitory activity(IC_(50) = 1.4 μM),which could be considered for Alzheimer's disease therapeutics. 相似文献
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Fatma H. Abd El-Salam 《Journal of Dispersion Science and Technology》2013,34(10):1362-1369
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. 相似文献
14.
One Pot Regioselective Synthesis and Antimicrobial Studies of Some Novel Indazolyl–Thiazole Derivatives
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2‐Benzylidene‐1‐tetralones, obtained via Claisen condensation of 1‐tetralones with aromatic aldehydes, in one pot condensation with thiosemicarbazide/semicarbazide and α‐haloketones in the presence of trifluoroethanol and conc. HCl gives rise to a series of new substituted‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazol‐2yl‐thiazoles. The condensation was also carried out in two steps, and the intermediates 3‐substituted‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazole‐2‐carbothioamides/carboxamides, obtained in the first step by the reaction of 2‐bezylidene‐1‐tetralones with thiosemicarbazide/semicarbazide, on reaction with α‐haloketones gives rise to indazolyl–thiazoles. A detailed X‐ray diffractometry of intermediate (3aR)‐3‐phenyl‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazole‐2‐carbothioamide were carried out to establish its crystal structure. Further, density functional theory studies on (3aR)‐3‐phenyl‐3,3a,4,5‐tetrahydro‐2H‐benzo[g]indazole‐2‐carbothioamide and its regioisomer were carried out. There is good correlation between the theoretical and experimental spectral data. The antibacterial and antifungal activities of the selected compounds were examined, and some are found to exhibit excellent activities. 相似文献
15.
A novel series of nonionic amino acid Schiff-Bases were synthesized and characterized using different spectroscopic tools to elucidate their chemical structures. The surface and thermodynamic properties of these compounds were studied using classical measurements including surface and interfacial tension and emulsification tendency. The surface parameters of these compounds including surface tension, critical micelle concentration (CMC), effectiveness (πcmc), efficiency (Pc20), maximum surface excess (Γmax), and minimum surface area (Amin) showed their good surface activity. Their thermodynamic parameters of adsorption and micellization including free energy change of micellization and adsorption showed their tendency toward adsorption at the interfaces and also micelle formation at lower concentrations. The synthesized compounds were also evaluated as corrosion inhibitors for carbon steel at different doses (400, 200, 100, 50, and 25 ppm) in 2 N HCl using gravimetric technique (weight loss). The results showed that these inhibitors are characterized by very high corrosion inhibition efficiency ranged between 99.93% and 97.98% and low corrosion rates varied between 0.09 mpy and 0.17 mpy for higher doses (400 ppm). The efficiency of inhibition was decreased by increasing the exposure time. The most efficient corrosion inhibitor of the synthesized compounds was the inhibitor which contains polyethylene oxide chain length of 23 EO units and alkyl chain length of 12 methylene groups. The effect of the hydrophobic and hydrophilic chain length in the inhibitor molecules was discussed and rationalized with their inhibition efficiency. The tendency of these inhibitors toward complexation with the transition metals was also discussed in order to explain their higher efficiency. 相似文献
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Nitin D. Gaikwad Sachin V. Patil Vivek D. Bobade 《Journal of heterocyclic chemistry》2013,50(3):519-527
A series of new 1‐[4‐(2,3,4‐substituted‐phenyl) thiazol‐2‐yl]‐3‐(2,3,4‐substituted‐phenyl)‐1H‐pyrazole‐4‐carbaldehyde ( 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j , 4k , 4l , 4m ), 4‐[4‐(4‐substituted‐phenyl) thiazol‐2‐yl]‐3‐(4‐substituted‐phenyl)‐1‐phenyl‐1H‐pyrazole ( 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i ), 4‐[4‐(4‐substituted phenyl)thiazol‐2‐yl]‐1‐phenyl‐1H‐pyrazol‐3‐amine ( 10a , 10b , 10c , 10d , 10e , 10f , 10g ) have been synthesized by using Vilsmeier Haack formylation and Hantzsch reaction in high yield. All the synthesized compounds were tested qualitative (Zone of inhibition) and quantitative antimicrobial activities (MIC). Most of the synthesized compounds showed potent antimicrobial activity against gram positive and gram negative bacteria as well as fungi species. 相似文献
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Although the organotransition metal fullerene-C60 derivatives have been intensively studied, no report regarding organochromium complexes containing a direct chromium to C60 bond has appeared in literatures.1 Now, we report preliminarily the synthesis, characterization and properties of the first such chromium complexes, namely single isomer fac-Cr(CO)3(dppe)(η2-C60) and the isomer mixture of fac- and mer-Cr(CO)3(dppe)(η2-C60). 相似文献
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Xian Chao CHENG Xin Yong LIU Wen Fang XU 《中国化学快报》2006,17(10):1317-1320
Ligustrazine (lig; tetramethylpyrazine, TMP; Figure 1) is one of major efficient components from Chinese traditional medicine herb Ligusticum Chuanxiong Hort, which is currently widely used in China for the treatment of coronary atherosclerotic cardiovasc… 相似文献