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Your search keyword '"Correia, Adriana N."' showing total 236 results
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236 results on '"Correia, Adriana N."'

10. Contributors

Author

Acevedo, R., primary, Ahamad, Tansir, additional, Akhtar, Naeem, additional, Altuntaş, Zübeyde Bayer, additional, Ananda Murthy, H.C., additional, Anbarasan, P.M., additional, Bayat, Ramazan, additional, Bekmezci, Muhammed, additional, Bindhu, S., additional, Boobas, S., additional, Çağlayan, Tahsin, additional, Canevari, Thiago C., additional, Chandrashekharappa, Sandeep, additional, Cheshideh, Hamed, additional, Correia, Adriana N., additional, de Lima-Neto, Pedro, additional, El-Said, Waleed A., additional, Ensafi, Ali A., additional, Erduran, Vildan, additional, Ferreira, Marystela, additional, Hari Krishna Charan, P., additional, Jayaprakash, Gururaj Kudur, additional, Kalikeri, Shankramma, additional, Kamal, Mostafa M., additional, Kapoor, Deepak, additional, Karthik, C.S., additional, Kaya, Hilmi Kaan, additional, Kazemifard, N., additional, Kumar, Deepak, additional, Kuralay, Filiz, additional, Maddiboyina, Balaji, additional, Mallu, P., additional, Manjunatha, J.G., additional, Miyazaki, Celina M., additional, Mohan, Yaamini, additional, Morais, Simone, additional, Moslehifard, Elnaz, additional, Mutyala, Sankararao, additional, Naga Mahesh, K., additional, Nagaswarupa, H.P., additional, Nalini, S., additional, Nandini, S., additional, Nasirpouri, Farzad, additional, Nasr-Esfahani, Parisa, additional, Nithin, K.S., additional, Oliveira, Thiago M.B.F., additional, Pandey, Rajat Kumar, additional, Priyadharsan, A., additional, Rajaram, Rajendran, additional, Rajendrachari, Shashanka, additional, Ramakrishna, Dileep, additional, Ramesh, R., additional, Rao, Srilatha, additional, Ravikumar, C.R., additional, Ribeiro, Francisco W.P., additional, Saberi, Z., additional, Safaei, Mohadeseh, additional, Sandeep, S., additional, Sen, Fatih, additional, Shanavas, S., additional, Shimizu, Flavio M., additional, Shishehbore, Masoud Reza, additional, Sivaraman, Gandhi, additional, Sneharani, A.H., additional, Sunaapu, OmPrakash, additional, Swetha, Puchakayala, additional, Tonk, Rajiv, additional, Torrinha, Álvaro, additional, and Wagassa, Ararso Nagari, additional

Published
2022
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28. Inhibition of Copper Corrosion in Acid Medium by Imidazole-Based Compounds: Electrochemical and Molecular Approaches

Author

Costa, Stefane N., Almeida-Neto, Francisco W. Q., Marinho, Emmanuel S., Campos, Othon S., Correia, Adriana N., and Lima-Neto, Pedro de

Subjects
imidazole derivatives, corrosion inhibitors, copper, H2SO4, density functional theory
Abstract

Chemically modified imidazole molecules: 4-(1H-imidazol-1-yl)aniline, 4-(1H-imidazol-1-yl)benzaldehyde, 4-(1H-imidazol-1-yl)phenol and (4-(1H-imidazol-1-yl)phenyl)methanol were investigated as inhibitors of the copper (Cu0) corrosion in 0.5 mol L-1 H2SO4 medium. The electrochemical corrosion data were obtained by monitoring open circuit potential, linear potentiodynamic polarization and electrochemical impedance spectroscopy techniques, while the computational density functional theory (DFT) method was applied to correlate the electronic properties of the molecules with corrosion inhibition efficiencies. All molecules had inhibited the Cu corrosion, and the inhibition values lied between 80 and 94%. A good correlation between the inhibition efficiencies values and Gibbs adsorption energy was found, showing that the more negative Gibbs energy, better interaction between the corrosion inhibitor with the Cu0 surface, diminishing its corrosion in 0.5 mol L-1 H2SO4 medium. The DFT calculations showed significative differences in electronic and reactivity properties of imidazole and other molecules. The higher corrosion inhibition of imidazole derivates could be explained by electrophilic characteristic of these molecules, since there are empty molecular orbitals spread over mainly in benzene rings that make a metal-ligand charge transfer, receiving electronic density from the copper surface by backbonding, according to the electronic Fukui functions and the potential charge distribution considering the map of electrostatic potential.

Published
2023

29. Square Wave Adsorptive Stripping Voltammetry Determination of Chlorpyriphos in Irrigation Agricultural Water

Author

Melo, Luisa C., Juliao, Murilo S.S., Milhome, Maria A.L., do Nascimento, Ronaldo F., De Souza, Djenaine, de Lima-Neto, Pedro, and Correia, Adriana N.

Subjects
Chlorpyrifos -- Measurement, Irrigation water -- Chemical properties, Voltammetry -- Usage, Chemistry
Abstract

This work describes the electroanalytical determination of Chlorpyriphos pesticide in natural waters using hanging mercury drop electrode allied to square wave adsorptive cathodic stripping voltammetry. The best responses were obtained in Britton-Robinson buffer solutions at pH 2.0, using a frequency of 100 [s.sup.-1], a scan increment of 5 mV, a square wave amplitude of 25 mV and an accumulation potential of -0.4 V during 60 s. Therefore, voltammetric responses showed the presence of one well-defined and irreversible reduction peak, at -1.08 V vs. Ag/AgCl/KCl 1.0 M, which involves two electrons in the reduction of carbon-nitrogen bond in the N-heterocyclic system with the participation of protonation equilibrium preceding the electron transfer reaction. Analytical curves were constructed and compared to similar curves performed by gas chromatograph coupled to a selective nitrogen-phosphorus detector, which demonstrates that the proposed methodology is suitable for determining contamination by Chlorpyriphos in complex samples. Keywords: Chlorpyriphos, organophosphorous pesticide, natural water, adsorptive square wave voltammetry, hanging mercury drop electrode, The Ceara State in Brazil is located in a semi-arid climate region that promotes irrigated agriculture to become the third largest producer and exporter of tropical fruits (melon, pineapple, papaya, [...]

Published
2018
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44. Effects of electrodeposition parameters on corrosion resistance of ZnSn coatings on carbon steel obtained from eutectic mixture based on choline chloride and ethylene glycol

Author

Pereira, Juliermes C., primary, dos Santos, Luis P.M., additional, Alcanfor, Ana A.C., additional, de Sant'Ana, Hosiberto B., additional, Feitosa, Felipe X., additional, Campos, Othon S., additional, Correia, Adriana N., additional, Casciano, Paulo N.S., additional, and de Lima-Neto, Pedro, additional

Published
2021
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46. Analytical determination of nimesulide and ofloxacin in pharmaceutical preparations using square-wave voltammetry

Author

Ribeiro, Francisco W.P., Soares, Thisiania R.V., Oliveira, Sameque do N., Melo, Luisa C., Soares, Janete E., Becker, Helena, De Souza, Djenaine, de Lima-Neto, Pedro, and Correia, Adriana N.

Subjects
Electrochemical reactions -- Research, Ofloxacin -- Research -- Dosage and administration, Voltammetry -- Research -- Usage, Chemistry
Abstract

The electrochemical behaviour and analytical detection procedure for nimesulide (NIM) and ofloxacin (OFX) and their assay in commercial formulations were evaluated using square-wave voltammetry (SWV) combined with a hanging mercury drop electrode (HMDE). All experimental and voltammetric conditions were previously optimized to obtain the best analytical signal in terms of intensities and profile of the reduction peaks. For NIM, the peak currents were related to the one-electron reduction of a nitro group to a stable radical anion, which is followed by a one-electron transfer and a protonation step with a consequent formation of a nitrosoanion. The voltammetric results indicated that the mechanism of OFX involved the transfer of two electrons and two protons in a totally irreversible reduction related to the conversion of a ketone group to an alcohol group. Analytical parameters such as linearity range, equations of the analytical curves, correlation coefficients, detection and quantification limits, recovery efficiency, and relative standard deviation for repeatability and reproducibility experiments were compared to similar results obtained by the use of UV-Vis spectrophotometry, and the results showed that the voltammetric procedure using HMDE is suitable to determine pharmaceutical compounds in complex samples. The applicability of the proposed procedure was tested on pharmaceutical formulations of NIM and OFX by observing the stability, specificity, recovery and precision of the procedure in tablets, oral solution and ophthalmic solution. Keywords: nimesulide, ofloxacin, square-wave voltammetry, pharmaceutical formulations, electrochemical behaviour DOI: 10.1134/S1061934814010079, The arrival of a great number of generic drugs, and, in particular, the appearance of various pharmaceutical laboratories, which are responsible for the research, production, distribution and commercialization of pharmaceutical [...]

Published
2014
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47. Preparation and characterization of electrodeposited iron + cobalt thin films from a chloride bath

Author

Correia Adriana N., Oliveira Regina C. B. de, and Lima-Neto Pedro de

Subjects
electrodeposition, anodic dissolution, Fe-Co thin films, Chemistry, QD1-999
Abstract

Fe-Co alloys were deposited and dissolved in the solution containing metallic ions and in the NH4Cl solution. Voltammetric results suggest interaction between the alloy components, constituting a solid solution. ALSV profiles show a differentiation for the dissolution process of the individual metals and alloys, with potentials displacement in the dissolution processes for more and more positive values, as the proportion of cobalt increases in the bath. The non-dimensional analyses of the potentiostatic transients for the cobalt, iron and Fe-Co 1:1 and 1:10 suggest a progressive nucleation. However, Fe-Co 1:5 allowed instantaneous nucleation. The chemical and physical characterization of the electrodeposits showed dependence between the surface morphology and the composition of the electrolytic bath. Besides, EDX analyses showed that the composition of the electrodeposits were always corresponding the chemical composition of the electrolytic bath. In this way, it was possible to classify these processes as regular deposition.

Published
2006

50. The effect of concentration on the electrocrystallization mechanism for copper on platinum ultramicroelectrodes

Author

Barin Cláudia S., Correia Adriana N., Machado Sérgio A. S., and Avaca Luis A.

Subjects
electrocrystallization, copper, Pt ultramicroelectrodes, atomistic theory, Chemistry, QD1-999
Abstract

The mechanism of copper electrocrystallization on Pt ultramicroelectrode surfaces has been studied by cyclic voltammetry, chronoamperometry and ex situ atomic force microscopy in acid solutions containing different Cu2+ concentrations. To analyze the potentiostatic transients a new model developed in our laboratories that takes into account spherical diffusion towards a disc-shaped ultramicroelectrode was used. A mechanistic change from progressive to instantaneous nucleation was observed when the Cu2+ concentration was increased from 0.01 to 0.1 mol dm-3. The shape and distribution of the nuclei formed on the surface were investigated by AFM. The dependence of the nucleation rate with potential was analyzed in terms of the atomistic theory of electrocrystallization and the results suggest the presence of only one copper atom in the critical nucleus.

Published
2000

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