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131.
Evaluation of some non-toxic thiadiazole derivatives as bronze corrosion inhibitors in aqueous solution 总被引:1,自引:0,他引:1
The inhibiting effect of four innoxious thiadiazole derivatives (2-mercapto-5-amino-1,3,4-thiadiazole (MAT), 2-mercapto-5-acetylamino-1,3,4-thiadiazole (MAcAT), 2-mercapto-5-methyl-1,3,4-thiadiazole (MMeT) and 2-mercapto-5-phenylamino-1,3,4-thiadiazole (MPhAT)) on bronze corrosion in an aerated solution of 0.2 g L−1 Na2SO4 + 0.2 g L−1 NaHCO3 at pH 5 was studied by potentiodynamic voltammetry and electrochemical impedance spectroscopy.The corrosion parameters determined from the polarisation curves indicate that the addition of the investigated thiadiazole derivatives decreases both cathodic and anodic current densities, due to an inhibition of the corrosion process, through the adsorption of thiadiazoles on the bronze surface. The inhibiting effect of the investigated organic compounds appears to be more pronounced on the anodic process than on the cathodic one and, except for the case MPhAT, it is enhanced by the increases of the inhibitors’ concentration.The adsorption of the thiadiazole derivatives on bronze was confirmed by the presence of the nitrogen atoms in the EDX spectra of the bronze exposed to inhibitor-containing solutions.The magnitude of polarisation resistance values and, consequently, the inhibition efficiencies are influenced by the molecular structure of thiadiazole derivatives. The strongest inhibition was noticed in the presence of compounds with phenyl amino- or amino-functionalities in their molecules. The maximum protection efficiencies were obtained by addition of: 5 mM MAT (95.9%), 1 mM MAcAT (95.7%), 5 mM MMeT (92.6%) and 0.1 mM MPhAT (97%). EIS measurements also revealed that the inhibitor effectiveness of the optimal concentrations of thiadiazole is time-dependent. 相似文献
132.
Jérôme Andrieux Dariusz Swierczynski Laetitia Laversenne Anthony Garron Simona Bennici Christelle Goutaudier Philippe Miele Aline Auroux Bernard Bonnetot 《International Journal of Hydrogen Energy》2009
In the present work, hydrogen generation through hydrolysis of a NaBH4(s)/catalyst(s) solid mixture was realized for the first time as a solid/liquid compact hydrogen storage system using Co nanoparticles as a model catalyst. The performance of the system was analysed from both the thermodynamic and kinetic points of view and compared with the classical catalyzed hydrolysis of a NaBH4 solution. The kinetic analysis of the NaBH4(s)/catalyst(s)/H2O(l) system shows that the reaction is first order with respect to the catalyst concentration, and the activation energy equal to 35 kJ molNaBH4−1. Additionally, calorimetric measurements of the heat evolved during the hydrolysis of NaBH4 solutions evidence the global process energy (−217 kJ molNaBH4−1). Characterization of the cobalt nanoparticles before and after the hydrolysis associated with the calorimetric measurements suggests the “in situ” formation of a catalytically active CoxB phase through “reduction” of an outer protective oxide layer that is regenerated at the end of reaction. 相似文献
133.
In this paper, the effect of different fuel injection strategies on the combustion process was investigated in a boosted port fuel injection spark-ignition engine. The experiments were performed on a partially transparent single-cylinder engine, equipped with a four-valve head and boost device. Single and double fuel injection strategies were tested in the open-valve condition. Moreover, two fuel injection pressures were considered. Optical techniques based on 2D-digital imaging were used to follow the flame propagation in the combustion chamber. In particular, the diffusion-controlled flames near valves and on cylinder walls due to the fuel film burning were studied. Two-colour pyrometry was employed to measure soot concentration. In-cylinder optical investigations were correlated to the engine parameters and to the exhaust emissions. 相似文献
134.
Simona Maggini Elisa CappellettoFabrizio Girardi Wilma VaonaRosa Di Maggio 《Progress in Organic Coatings》2013
Silica based cellulose nanocomposites obtained from (3-mercaptopropyl)trimethoxysilane or vinyltrimethoxysilane and 3-butynoate-substituted zirconium-oxoclusters were prepared and their surface morphology, wettability, and thermo-mechanical properties were studied. The composites showed a hydrophobic surface, high strength, and resistance to thermal degradation and aging; in comparison to the untreated paper they required a higher temperature to activate combustion and generated less heat during all thermal processes. 相似文献
135.
Sarunas Varnagiris Jolanta Doneliene Simona Tuckute Jurate Cesniene Darius Milcius 《Polymer-Plastics Technology and Engineering》2018,57(13):1296-1302
Conventional expanded polystyrene can absorb moisture, which significantly degrades its properties. In the present study, it was demonstrated that SiO2 can be deposited on polystyrene beads before pre-expansion and molding steps. Under the applied test conditions, expanded polystyrene with nanocrystalline SiO2 additives had approximately 10% lower moisture adsorption and an 8.4% better resistance to deformation. Expanded polystyrene analysis suggested that the observed improvements were caused by the hydrophobic nature of nanocrystalline SiO2 and, even more importantly, because SiO2 acted as an amalgamation catalyst and significantly increased adhesion between the expanded polystyrene beads during the expanded polystyrene molding process. 相似文献
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139.
Anca Giorgiana Grigoras Marieta Constantin Vasile Cristian Grigoras Simona Isabela Dunca Lacramioara Ochiuz 《Reactive and Functional Polymers》2013,73(9):1249-1254
The physico-chemical properties of three grafted pullulans (P) having linked poly(3-acrylamidopropyl)trimethylammonium chloride (pAPTAC) as side chains (P-g-pAPTAC1, P-g-pAPTAC2 and P-g-pAPTAC3 with 22.53, 29.05, and 34.51 (wt.%) of pAPTAC content in polymer, respectively) and possessing polyelectrolyte character were determined by light scattering analysis. All grafted pullulan aqueous solutions were tested in the presence of 0.5 M NaCl, KCl, NaNO3 or KNO3. The biggest associations were recorded in 0.5 M NaCl aqueous solutions for P-g-pAPTAC1, P-g-pAPTAC2 and P-g-pAPTAC3 according to the maximum values for Rg extracted from MALLS (multiangle laser light scattering) measurements. Also, the dominant conformation in salted solution of these polyelectrolytes was random coil as Debye plot analysis revealed. Antibacterial activity was tested by Kirby–Bauer diffusion method and all grafted pullulans dissolved in aqueous solutions of 0.5 M NaCl have developed inhibition zone against Staphylococcus aureus (ATCC 25923). 相似文献
140.
Iva Blazkova Hoai Viet Nguyen Simona Dostalova Pavel Kopel Maja Stanisavljevic Marketa Vaculovicova Marie Stiborova Tomas Eckschlager Rene Kizek Vojtech Adam 《International journal of molecular sciences》2013,14(7):13391-13402
Magnetic particle mediated transport in combination with nanomaterial based drug carrier has a great potential for targeted cancer therapy. In this study, doxorubicin encapsulation into the apoferritin and its conjugation with magnetic particles was investigated by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). The quantification of encapsulated doxorubicin was performed by fluorescence spectroscopy and compared to CE-LIF. Moreover, the significant enhancement of the doxorubicin signal was observed by addition of methanol into the sample solution. 相似文献