6 resultados para 1,3,4-triazólio-2-tiolato

em Universidade Federal do Rio Grande do Norte(UFRN)


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The efficiency of inhibition to corrosion of steel AISI 1018 of surfactant coconut oil saponified (SCO) and heterocyclic type mesoionics (1,3,4-triazólio-2-tiolato) in systems microemulsionados (SCO-ME and SCO-ME-MI) Of type O/A (rich in water emulsion) region with the work of Winsor IV. The systems microemulsionados (SCO-ME and SCO-ME-MI) were evaluated with a corrosion inhibitor for use in saline 10,000 ppm of chloride enriched with carbon dioxide (CO2). The assessment of corrosion inhibitors were evaluated by the techniques of linear polarization resistance (LPR) and loss of weight (MW) in a cell instrumented given the gravity and electrochemical devices. The systems were shooting speed of less than 60 minutes and efficiency of inhibition [SCO-ME (91.25%) and SCO-ME-MI (98.54%)]

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Corrosion inhibition efficiency of saponified coconut oil (SCO) and sodium dodecilbenzene sulfonate (DBS) surfactants in AISI 1020 carbon steel was evaluated by electrochemical methods. These surfactants were also evaluated as microemulsion systems (SCO-ME and DBS-ME), of O/W type (water-rich microemulsion), in a Winsor IV region. They were obtained according to the following composition: 15% SCO, 15% butanol (30% Co-surfactant/Surfactant C/T), 10% organic phase (FO, kerosene) and 60% aqueous phase (FA). These systems were also used to solubilize the following nitrogenated substances: Diphenylcarbazide (DC), 2,4-dinitro-phenyl-thiosemicarbazide (TSC) and the mesoionic type compound 1,3,4-triazolium-2-thiolate (MI), that were investigated with the purpose of evaluating their anticorrosive effects. Comparative studies of carbon steel corrosion inhibition efficiencies of free DBS and DBS-ME, in brine and acidic media (0.5%), showed that DBS presents better inhibition results in acidic media (free DBS, 89% and DBS-ME, 93%). However, the values obtained for DBS in salted solution (72% free DBS and 77% DBS-ME) were similar to the ones observed for the SCO surfactant in brine (63% free SCO and 74% SCO-ME). Analysis of corrosion inhibition of the nitrogenated substances that were solubilized in the SCO-ME microemulsion system by the linear polarization method in brine (0.5% NaCl) showed that such compounds are very efficient an corrosion inhibitors [DC-ME-SCO (92%), TSC-ME-SCO (93%) and MI-ME-SCO (94%)]

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The efficiency of inhibition to corrosion of steel AISI 1018 of surfactant coconut oil saponified (SCO) and heterocyclic type mesoionics (1,3,4-triazólio-2-tiolato) in systems microemulsionados (SCO-ME and SCO-ME-MI) Of type O/A (rich in water emulsion) region with the work of Winsor IV. The systems microemulsionados (SCO-ME and SCO-ME-MI) were evaluated with a corrosion inhibitor for use in saline 10,000 ppm of chloride enriched with carbon dioxide (CO2). The assessment of corrosion inhibitors were evaluated by the techniques of linear polarization resistance (LPR) and loss of weight (MW) in a cell instrumented given the gravity and electrochemical devices. The systems were shooting speed of less than 60 minutes and efficiency of inhibition [SCO-ME (91.25%) and SCO-ME-MI (98.54%)]

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Several studies are carried out with aim to establish parameters to determine biologic behavior of oral squamous cell carcinoma, in order this neoplasm presents high rates of morbidity and mortality. The purpose of present research was to performe a clinic, morphologic and immunohistochemical analysis by the expression of galectins 1, 3, 4 and 7 in 65 cases of tongue squamous cell carcinoma, correlating this expression with clinics (outcome of the disease, metastasis and clinical staging) and morphologic parameters (malignancy histologic gradation system). The clinical and morphologic parameters analysed and expression of galectins 1, 3, 4 and 7 were submitted to statistical analysis (Qui2 test), observing that can be utilized as indicators of the biological behavior of the tongue squamous cell carcinoma. The galectin 1 was expressed in 87,7% of cases studied and it exhibit statistically significant correlation with metastasis (p=0,033) and clinical staging (p=0,016), it is located mostly in the citoplasm of the stomal cells. The immunoexpression of galectin 3 in 87,7% of cases was correlated with the presence of metastasis (p=0,033) and malignancy histological gradation system (p=0,031), observed, mostly of cases, in tongue squamous cell carcinoma of malignancy high grading. The galectin 4 showed no statistical significance to any of the parameters evaluated. The expression of galectin 7 in 73,8% of cases showed statistically significant correlation with the malignancy histologic grading (p=0,005), which is marking exclusively found in neoplastic epithelial cells, in the mostly of cases, it is found in cytoplasm and membrane (50%). The expressive immunopositivy of the galectins 1, 3 and 7, observed in this research, leads us to suggest a broad participation of these proteins in oral carcinogenesis, and its possible use as markers of biological behavior and tumor progression in cases of squamous cell carcinoma of the tongue

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Introdução: A displasia epitelial oral (DEO) é uma lesão potencialmente maligna, cujo diagnóstico e gradação se baseia na histologia das alterações arquiteturais e citológicas, preconizados pela OMS, que divide a lesão em leve, moderada e severa, o qual é subjetivo. Maior concordância é observada no uso do sistema binário (baixo/alto risco), o qual está relacionado ao risco de transformação maligna. As galectinas constituem uma família de lectinas e estão envolvidas na tumorigênese, sendo a -1, -3 e -7 as mais investigadas, devido a expressão alterada em cânceres orais. Materiais e métodos: Foi analisada a expressão imuno-histoquímica dessas proteínas em 50 espécimes de DEO (21 baixo/ 29 alto risco) e 5 de mucosa oral normal e relacionamos com a presença/ausência de marcação, padrão de distribuição, intensidade, localização epitelial (estratificação) (1/3 inferior, médio e superior), e localização celular (compartimento) (núcleo, citoplasma e membrana) . Resultados: Dos 29 casos de alto e dos 21 de baixo risco, 21 (72,4%) e 12 (57,1%) foram positivos para a galectina -1, respectivamente. Dessa forma, de 50 casos, 33 foram positivos. O núcleo e citoplasma foram positivos em 91,7% nas de baixo risco e em 90,5% nas de alto. Todos os casos de mucosa normal foram negativos. Com relação a galectina -3, dos 21 casos das DEOs de baixo risco, 12 (57,1%) apresentaram expressão e dos 29 casos das DEOs de alto risco, 15 (51,7%) foram positivos, havendo imunoexpressão em um total de 27 casos. O padrão difuso, assim como a fraca intensidade foram os mais freqüentes para os 2 graus. O núcleo e o citoplasma foram a localização mais comum tanto nas lesões de baixo (58,3%), quanto nas de alto risco (66,7%). Quatro casos de mucosa normal foram positivos, com marcação membranar e intensidade fraca. Dos 21 casos das DEOs de baixo risco, 17 (81%) apresentaram expressão imuno-histoquímica para a galectina -7 e das 29 DEOs de alto risco, 27 (93,1%) foram positivos. Então, a expressão imuno-histoquímica da galectina -7 foi observada em 44 casos, a maioria com intensidade de moderada a forte. O núcleo e o citoplasma foram a localização mais freqüente, nas de baixo (70,6%) e alto risco (66,7%). Quatro espécimes de mucosa normal marcaram membrana em terço médio e superior, com intensidade moderada a forte. Conclusões: Alterações na expressão das galectinas -3 e -7 e principalmente da -1 sugerem seu envolvimento na fisiopatologia das displasias, participando do processo de transformação de fenótipo normal para o displásico.

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This is a work involving fundamental studies of chemistry where the synthesis and structural characterization, as well as a possible future application of these new compounds as luminescent sensors or sunscreen agents, complexes with 4,4 diaminostilbene-2,2-disulfonic (DSD) and trivalent lanthanide ions La3+, Nd3+, Eu3+, Gd3+ and Yb3+, were synthesized in the ratio of 3 mmol: 1 mmol (DSD: lanthanides). The complexes obtained with these ions were present in powder form and were characterized by complexometric titration with EDTA CHN Elemental analysis, molecular absorption spectroscopy in the ultraviolet region, the absorption spectroscopy in the infrared, thermal analysis (TG / DTG), Nuclear Magnetic Resonance - NMR 1H and Luminescence Spectroscopy. The complexometric titration and CHN analysis, confirmed the TG / DTG which suggest that these complexes have the following general chemical formulas: [La2(C14H12S2O6N2)2(H2O)2Cl2].7H2O,[Nd2(C14H12S2O6N2)2(H2O)2Cl2].6H2O,[Eu2(C14 H12S2O6N2)2(H2O)2Cl2].7H2O,[Gd2(C14H12S2O6N2)2(H2O)2Cl2].4H2O e [Yb2(C14H12S2O6N2)2(H2O)2].6H2O. The disappearance of the bands in the infrared spectrum at 2921 cm-1 and 2623 cm-1 and the displacement of the bands in the spectra of the amine complex indicate that the lanthanide ion is coordinated to the oxygen atoms and the sulfonate groups of the nitrogens amines, suggesting the formation of the dimer. The disappearance of the signal and the displacement signal SO3H amines in the 1H NMR spectrum of this complex are also indicative coordination and dimer formation. The Thermogravimetry indicates that the DSD is thermally stable in the range of 40º to 385°C and their complexes with lanthanide ions exhibit weight loss between 4 and 5 stages. The Uv-visible spectra indicated that the DSD and complexes exhibit cis isomers. The analysis of luminescence indicates that the complexes do not exhibit emission in the region of the lanthanides but an intense emission part of the binder. This is related to the triplet states of the ligand, which are in the lowest energy state emitting lanthanide ions, and also the formation of the dimer that suppress the luminescence of ion Eu3+. The formation of dimer was also confirmed by calculating the europium complex structure using the model Hamiltonian PM6 and Sparkle