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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 37-46页

作者： M.Yadav Debasis Behera R.R.Sinha P.N.Yadav Department of Applied Chemistry Indian School of Mines Department of Physics Post Graduate College

The inhibition effect of synthesized diethyl 3,4-bis（4-methoxybenzylideneamino） thieno[2,3-b] thiophene-2,5- dicarboxylate （Inh I） and diethyl 3,4-bis（benzylideneamino） thieno[2,3-b] thiophene-2,5-dicarboxylate （Inh II）, on cor- rosion of mild steel in 15% HC1 solution was investigated using weight loss measurements, electrochemical polarization, and electrochemical impedance spectroscopy techniques. The experimental results show that the inhibition efficiency of studied inhibitors increased with the increase of inhibitors concentration but decreased with the increase of temperature. Corrosion inhibition efficiencies of 94.5% and 92.1% were obtained with 250 ppm of Inh I and Inh II at 303 K, respectively. The potentiodynamic polarization measurements indicate that the studied inhibitors act as mixed inhibitor. The thermodynamic parameters of the corrosion and adsorption processes were calculated and evaluated. The adsorption of these inhibitors was found to obey Langmuir adsorption isotherm. Scanning electron microscopy was used to characterize the surface morphology of the mild steel specimens in presence and absence of inhibitors. The mechanism of the inhibition process was discussed in the light of the chemical structure and quantum-chemical calculations of the investigated inhibitors.

关键词： Mild steel Corrosion Polarization EIS acid inhibition

Three novel dendritic chitosan derivatives for inhibiting acid corrosion of petroleum pipelines

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Petroleum Science 2023年第6期20卷 3918-3930页

作者： Guo-Dong Cui Yan-Ming Chen Qi-Ming Zhang Zheng Wang Tian Tang Qing Zhao Yu Zhang Li-Feng Zhang Yuan-Qi Gu Yang-Sheng Liu College of Environmental Sciences and Engineering Peking UniversityBeijing Key Laboratory for Solid Waste Utilization and ManagementBeijing100871China University of Houston HoustonTX77204United States State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing102249China CenerTech Tianjin Chemical Research and Design Institute Co. LtdChina National Offshore Oil Corp(CNOOC)Tianjin300131China Faculty of Environment and Life Beijing University of TechnologyBeijing100124China Shanxi International Energy Group Co. LtdTaiyuan030002ShanxiChina

In the process of exploration and development of oil and gas fields, the acidic environment of oil reservoir, production and transport processes cause corrosion of pipelines and equipment, resulting in huge economic losses and production safety risks. Corrosion inhibitors were widely used in oil industry because of simple operation process and economical. In this study, three environmentally friendly corrosion inhibitors were synthesized based on the natural polysaccharide chitosan. Corrosion inhibition of three dendritic chitosan derivatives (We name them BH, CH and DH) on mild steel in 1 mol/L HCl solution with natural ventilation system was evaluated by weight loss experiment, electrochemical analysis and surface morphology characterization. The experimental results showed that when the three dendritic chitosan derivatives added in the corrosive medium were 500 mg L^(−1), the corrosion inhibition efficiencies were all more than 80%. Based on quantum chemical calculation, inhibition mechanisms of three dendritic chitosan derivatives were investigated according to molecular structures. The results showed that the benzene ring, Schiff base and N atom contained in the molecule were the active centers of electron exchange, which were more likely to form a film on the carbon steel surface, thereby slowing or inhibiting corrosion. The results also predicted the corrosion inhibition effect BH > DH > CH, which was consistent with the experimental conclusion.

关键词： Chitosan derivatives Corrosion inhibitors Carbon steel acid inhibition Efficient and environmental

1,4-Bis(2-nitrobenzylidene) thiosemicarbazide as Effective Corrosion Inhibitor for Mild Steel

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Journal of Materials Science & Technology 2013年第11期29卷 1096-1100页

作者： P.Mohan G.Paruthimal Kalaignan Advanced Materials Research Lab Department of Industrial ChemistryAlagappa University

The inhibition efficiency of 1,4-bis （2-nitrobenzylidene） thiosemicarbazide （BBTS） on the corrosion of mild steel in 1 mol/L HCI was investigated by potentiodynamic polarization and electrochemical impedance methods. inhibition efficiency （IE）, corrosion rate and surface coverage were evaluated at different concentrations of BBTS. The results of the investigation showed that this compound had good inhibiting properties for mild steel corrosion in hydrochloric acid and BBTS was a mixed-type inhibitor. BBTS chemisorbed at the electrode surface obeyed Langmuir adsorption isotherm and formed a stable surface complex on the mild steel surface. The synergistic effect of halide ion in acid solution suggested a co-adsorption of BBTS inhibitor by the adsorbed iodide ion.

关键词： acid inhibition Polarization Langmuir adsorption Electrochemical impedance spectroscopy (EIS)

Safety of the long-term use of proton pump inhibitors

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World Journal of Gastroenterology 2010年第19期16卷 2323-2330页

作者： Alan BR Thomson Michel D Sauve Narmin Kassam Holly Kamitakahara Division of General Internal Medicine Faculty of Medicine University of Alberta Edmonton AB T6G 2B7 Alberta Canada

The proton pump inhibitors (PPIs) as a class are remarkably safe and effective for persons with peptic ulcer disorders. Serious adverse events are extremely rare for PPIs, with case reports of interstitial nephritis with omeprazole, hepatitis with omeprazole and lansoprazole, and disputed visual disturbances with pantoprazole and omeprazole. PPI use is associated with the development of fundic gland polyps (FGP); stopping PPIs is associated with regression of FGP. In the absence of Helicobacter pylori infection, the long-term use of PPIs has not been convincingly proven to cause or be associated with the progression of pre-existing chronic gastritis or gastric atrophy or intestinal metaplasia. Mild/modest hypergastrinemia is a physiological response to the reduction in gastric acid secretion due to any cause. The long-term use of PPIs has not been convincingly proven to cause enterochromaff in-like cell hyperplasia or carcinoid tumors. PPIs increase the risk of community acquired pneumonia, but not of hospital acquired (nosocomial) pneumonia. There is no data to support particular care in prescribing PPI therapy due to concerns about risk of hip fracture with the long-termuse of PPIs. Long-term use of PPIs does not lead to vitamin B12 def iciencies, except possibly in the elderly, or in persons with Zollinger-Ellison Syndrome who are on high doses of PPI for prolonged periods of time. There is no convincingly proven data that PPIs increase the risk of Clostridium difficile-associated diarrhea in persons in the community. The discontinuation of PPIs may result in rebound symptoms requiring further and even continuous PPI use for suppression of symptoms. As with all medications, the key is to use PPIs only when clearly indicated, and to reassess continued use so that long-term therapy is used judiciously. Thus, in summary, the PPIs are a safe class of medications to use longterm in persons in whom there is a clear need for the maintenance of extensive acid inhibition.

关键词： acid inhibition Drug safety Osteoporosis Pneumonia Enteric infections

Cocos nucifera *** as green corrosion inhibitor for acid corrosion of aluminium in HCl solution

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Chinese Chemical Letters 2010年第12期21卷 1449-1452页

作者： Olusegun K.Abiola Y.Tobun Department of Chemistry Federal University of Petroleum ResourcesEffurunNigeria Department of Chemistry University of LagosAkokaLagosNigeria

The ability of Cocos nucifera ***（CW） as non-toxic corrosion inhibitor for acid corrosion of aluminium in 0.5 mol/L HCl has been studied using chemical *** shows significant inhibition as corrosion inhibitor,with 93%efficiency at the highest concentration of the *** inhibitive action is attributed to the adsorption of the inhibitor molecules on metal surface following Langmuir adsorption isotherm.

关键词： Cocos nucifera L. water acid inhibition Green inhibitor Aluminium Weight loss