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Previous issue date: 2013-01-21 / Corrosion is a natural process that causes progressive deterioration of materials, so,
reducing the corrosive effects is a major objective of development of scientific studies. In this
work, the efficiency of corrosion inhibition on a AISI 1018 carbon steel of the nanoemulsion
system containing the oil of the seeds of Azadirachta indica A. Juss (SNEOAI) was evaluated
by the techniques of linear polarization resistance (LPR) and weight loss (CPM), a
instrumented cell. For that, hydroalcoholic extract of leaves of A. indica (EAI) was
solubilized in a nanoemulsion system (SNEOAI) of which O/W system (rich in aqueous
phase). This nanoemulsion system (tested in different concentrations) was obtained with oil
from the seeds of this plant species (OAI) (oil phase), dodecylammonium chloride (DDAC)
(surfactant), butanol (cosurfactant) and water, using 30 % of C/T (cosurfactant/surfactant), 0.5
% of oil phase and 69.5 % of aqueous phase, and characterized by surface tension, rheology
and droplet sizes. This systems SNEOAI and SNEOAI-EAI (nanoemulsion containing
hydroalcoholic extract - EAI) showed inhibition efficiencies in corrosive environment in
saline (1 %), for the method of LPR with significant value of 70.58 % (300 ppm) to SNEOAI,
74.17 % (100 ppm) and 72.51 % (150 ppm) to SNEOAI-EAI. The best efficiencies inhibitions
were observed for the method of CPM with 85.41 % for the SNEOAI (300 ppm) and 83.19 %
SNEOAI-EAI (500 ppm). The results show that this formulation could be used commercially
for use as a corrosion inhibitor, this research contributed to the biotechnological applicability
of Azadirachta indica, considering the large use of this plant species rich in limonoids
(tetranortriterpenoids), especially azadirachtin / A corros?o ? um processo natural que causa a deteriora??o progressiva dos materiais,
neste sentido, diminuir os efeitos corrosivos ? um dos principais objetivos do
desenvolvimento de diversas pesquisas cient?ficas. Neste trabalho, a efici?ncia de inibi??o ?
corros?o em a?o AISI 1018 do sistema nanoemulsionado contendo o ?leo das sementes de
Azadirachta indica A. Juss (SNEOAI) foi avaliada pelas t?cnicas de resist?ncia a polariza??o
linear (LPR) e perda de massa (CPM), em uma c?lula instrumentada. Para tanto, o extrato
hidroalco?lico das folhas de A. indica (EAI) foi solubilizado em um sistema nanoemulsionado
(SNEOAI) do tipo O/A (rico em ?gua). Este sistema nanoemulsionado (testado em diferentes
concentra??es), foi obtido a partir do ?leo das sementes desta esp?cie vegetal (OAI) (fase
?leo), cloreto de dodecilam?nio (DDAC) (tensoativo), butanol (cotensoativo), e ?gua, nas
seguintes propor??es: 30 % de C/T (cotensoativo/tensoativo), 0,5 % de fase ?leo e 69,5 % de
fase aquosa, e caracterizado por tens?o superficial, comportamento reol?gico e di?metro de
got?culas. Os sistemas SNEOAI e SNEOAI-EAI (nanoemuls?o contendo o extrato EAI)
apresentaram efici?ncias de inibi??es, em meio corrosivo salino (1 %), para o m?todo de LPR
com m?ximas de 70,58 % (300 ppm) para SNEOAI e para o extrato nanoemulsionado
(SNEOAI-EAI) observou-se 74,17 % (100 ppm) e 72,51 % (150 ppm). As melhores
efici?ncias de inibi??es foram observadas pelo m?todo CPM com 85,41 % para SNEOAI (300
ppm) e 83,19 % para SNEOAI-EAI (500 ppm). Os resultados comprovam que esta
formula??o poder? vir a ser utilizada comercialmente como inibidor de corros?o, dessa forma,
a presente pesquisa contribuiu para as aplicabilidades biotecnol?gicas de Azadirachta indica,
considerando o amplo uso desta esp?cie vegetal rica em limon?ides (tetranortriterpen?ides),
com destaque para a azadiractina
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17708 |
| Date | 21 January 2013 |
| Creators | Emerenciano, Denise Pofirio |
| Contributors | CPF:31482015404, http://lattes.cnpq.br/2959800336802498, Maciel, Maria Aparecida Medeiros, CPF:37320165449, http://lattes.cnpq.br/5360188002708095, Neves, Aurea Echevarria Aznar, CPF:66874238868, Rossi, C?tia Guaraciara Fernandes Teixeira, CPF:77044568491, http://lattes.cnpq.br/0103853142184734, Moura, Maria de F?tima Vit?ria de |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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