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You searched for +publisher:"Universidade Federal Rural do Rio de Janeiro; Programa de P?s-Gradua??o em Qu?mica; UFRRJ; Brasil; Instituto de Ci?ncias Exatas" +contributor:("Santos, Margareth L. Santos"). One record found.

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1. Rodrigues, Arthur Valbon. <em class="hilite"><em class="hilite">Sem>em>?ntese e avalia??<em class="hilite">oem> anticorrosiva experimental e te?rica <em class="hilite"><em class="hilite">deem>em> tioureias assim?tricas derivadas da benzil e fenetilamina.

Degree: 2015, Universidade Federal Rural do Rio de Janeiro; Programa de P?s-Gradua??o em Qu?mica; UFRRJ; Brasil; Instituto de Ci?ncias Exatas

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Made available in DSpace on 2017-03-21T13:39:54Z (GMT). No. of bitstreams: 1 2015 - Arthur Valbon Rodrigues.pdf: 2339821 bytes, checksum: 867f44f511f5a52dfdcf023619e589a9 (MD5) Previous issue date: 2015-08-04

Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES

In this work six asymmetric thyourea, derived from benzylamine and phenethylamine, were synthesized by reaction of p-substituted phenyl isothiocyanates in the presence of benzylamine and phenethylamine in toluene as solvent by irradiation in ultrasonic bath, featuring the first report in the literature of the adoption of this method for such molecules. The compounds were obtained in high purity, requiring only one recrystallization from hexane/dichloromethane. Yields were very satisfactory, ranging from 89 to 98%. The compounds were characterized by spectroscopic techniques such as 1H, 13C Nuclear Magnetic Resonance and IR. The synthesized compounds were evaluated by electrochemical potentiodynamic polarization techniques, Electrochemical Impedance Spectroscopy and Linear Polarization Resistance as inhibitors to the corrosion AISI 1020 carbon steel in 1M HCl media. Molecular modeling was used for better visualization of the thiourea structures and to correlate theoretical parameters such as the energy of the symmetrical frontier orbital, Mulliken charge on the sulfur atom and dipole moment with the experimental results for corrosion efficiency. In general, all compounds showed corrosion inhibition efficiency with characteristics of mixed inhibitors with anodic trend, however compounds with nitro substituent showed less efficiency, a fact that may be related to their electrons withdrawing potential, which consequently decreases the electron density at the possible center of chemical adsorption, the sulfur atom. However, compounds which showed no substituent and those that contain electron donating group (OCH3) stood out as inhibitors, highlighting N- (p-methoxyphenyl) -N'-phenetylthiourea, which showed 95% efficiency corrosion inhibition, from Electrochemical Impedance spectroscopy. Thus, the asymmetric thiourea benzyl and phenethyl-substituted, especially methoxy-substituted phenyl, can be considered as promising corrosion inhibitors for carbon steel in acid.

Nesse trabalho de disserta??o foram sintetizadas seis tioureias assim?tricas, derivadas da benzilamina e fenetilamina. A obten??o ocorreu atrav?s da rea??o dos isotiocianatos de fenila p-substituidos na presen?a da benzilamina e fenetilamina em tolueno como solvente atrav?s de irradia??o em banho de ultrassom, sendo o primeiro relato na literatura dessa metodologia para tais mol?culas. Os compostos foram obtidos em alto grau de pureza, sendo necess?ria apenas uma recristaliza??o em hexano/diclorometano. Os rendimentos foram muitos satisfat?rios, variando de 89 ? 98%. Os compostos foram…

Advisors/Committee Members: Lima, Aurea Echevarria Aznar Neves, D'Elia, Eliane, Agostinho, Silvia Maria Leite, Santos, Margareth L. Santos.

Subjects/Keywords: Thiourea; Organic Corrosion Inhibitors; Molecular Modeling; Electrochemical Impedance Spectroscopy; Linear Polarization Resistance; Tioureia, , , ,; Inibidores Org?nicos de Corros?o; Modelagem Molecular; Espectroscopia de Imped?ncia Eletroqu?mica; Resist?ncia de Polariza??o Linear; Ci?ncias Exatas e da Terra

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APA (6th Edition):

Rodrigues, A. V. (2015). S?ntese e avalia??o anticorrosiva experimental e te?rica de tioureias assim?tricas derivadas da benzil e fenetilamina. (Masters Thesis). Universidade Federal Rural do Rio de Janeiro; Programa de P?s-Gradua??o em Qu?mica; UFRRJ; Brasil; Instituto de Ci?ncias Exatas. Retrieved from https://tede.ufrrj.br/jspui/handle/jspui/1470

Chicago Manual of Style (16th Edition):

Rodrigues, Arthur Valbon. “S?ntese e avalia??o anticorrosiva experimental e te?rica de tioureias assim?tricas derivadas da benzil e fenetilamina.” 2015. Masters Thesis, Universidade Federal Rural do Rio de Janeiro; Programa de P?s-Gradua??o em Qu?mica; UFRRJ; Brasil; Instituto de Ci?ncias Exatas. Accessed May 08, 2021. https://tede.ufrrj.br/jspui/handle/jspui/1470.

MLA Handbook (7th Edition):

Rodrigues, Arthur Valbon. “S?ntese e avalia??o anticorrosiva experimental e te?rica de tioureias assim?tricas derivadas da benzil e fenetilamina.” 2015. Web. 08 May 2021.

Vancouver:

Rodrigues AV. S?ntese e avalia??o anticorrosiva experimental e te?rica de tioureias assim?tricas derivadas da benzil e fenetilamina. [Internet] [Masters thesis]. Universidade Federal Rural do Rio de Janeiro; Programa de P?s-Gradua??o em Qu?mica; UFRRJ; Brasil; Instituto de Ci?ncias Exatas; 2015. [cited 2021 May 08]. Available from: https://tede.ufrrj.br/jspui/handle/jspui/1470.

Council of Science Editors:

Rodrigues AV. S?ntese e avalia??o anticorrosiva experimental e te?rica de tioureias assim?tricas derivadas da benzil e fenetilamina. [Masters Thesis]. Universidade Federal Rural do Rio de Janeiro; Programa de P?s-Gradua??o em Qu?mica; UFRRJ; Brasil; Instituto de Ci?ncias Exatas; 2015. Available from: https://tede.ufrrj.br/jspui/handle/jspui/1470

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