Papers by Vesna Mišković-Stanković
2015 IEEE 15th International Conference on Bioinformatics and Bioengineering (BIBE), 2015
Alginate nanocomposite hydrogels with incorporated electrochemically synthesized silver nanoparti... more Alginate nanocomposite hydrogels with incorporated electrochemically synthesized silver nanoparticles were investigated regarding cytotoxicity in vitro. Direct contact test of Ag/alginate discs was applied in 2D monolayer cultures of bovine calf chondrocytes while a 3D culture of bovine articular cartilage explants pressed by the discs was established in a biomimetic bioreactor with dynamic compression in the physiological regime (10 % strain, 0.84 Hz frequency, 1 h on / 1 h off). Moderate cytotoxicity was observed in 2D cell cultures as opposed to findings in 3D explant cultures, which were not affected by the Ag/alginate discs despite the compression.
Progress in Organic Coatings, 1994
... Experimental Commercial protective coatings on phosphatized galvanized steel, based on epoxy ... more ... Experimental Commercial protective coatings on phosphatized galvanized steel, based on epoxy resin (total thickness ... which represents the extent of ionic conduction through the polymer in electrolytic ... it represents a heterogeneous assembly of elec-trolytically conducting paths ...
Materials Science Forum, 2004
ABSTRACT
On a developpe un traitement pour diminuer l'adherence des salissures sur les surfaces peinte... more On a developpe un traitement pour diminuer l'adherence des salissures sur les surfaces peintes a faible brillant dans la construction aeronautique militaire. Ce traitement utilise une solution aqueuse contenant de la silice colloidale. Des essais de laboratoire montrent la durabilite du traitement apres exposition au brouillard salin et a differents fluides agressifs.
On a electrodepose sur de l'acier des films d'alumine, a partir de suspensions aqueuses, ... more On a electrodepose sur de l'acier des films d'alumine, a partir de suspensions aqueuses, en employant la methode du voltage constant. On a etudie la morphologie des films deposes par microscopie optique couplee a l'analyse d'images, ce qui permet la determination du nombre de pores, du pourcentage de la surface du film couvert par les pores et du diametre moyen de ces pores, et on a aussi utilise la microscopie electronique. On observe que la concentration de poudre d'alumine en suspension dans l'eau a un effet marque sur la morphologie des films deposes. La porosite minimale des films a ete obtenue pour le plus bas voltage (30 V) et la plus longue duree de deposition (10 min), ceci a partir de suspensions ayant la meilleure dispersion de particules (20 % en masse de poudre d'alumine).
Progress in Organic Coatings, 2005
The corrosion behavior of mild steel and mild steel covered by electrochemically deposited (a) po... more The corrosion behavior of mild steel and mild steel covered by electrochemically deposited (a) polyaniline (PANI) film, (b) epoxy coating and (c) PANI/epoxy coating system in 0.1M sulfuric acid solution were investigated by electrochemical impedance spectroscopy (EIS). Electrochemical deposition of PANI film was performed from aqueous solution of 0.5M sodium benzoate and 0.1M aniline at constant current density of 1.5mAcm−2.
Surface and Coatings Technology, 2014
ABSTRACT Among potential replacements for chromates, cerium-based conversion coatings (CeCCs) hav... more ABSTRACT Among potential replacements for chromates, cerium-based conversion coatings (CeCCs) have been identified as leading candidates, showing a good promise as environmentally compliant corrosion inhibitors on Al alloys. In this work, CeCCs were synthesized on AA6060 by electrolytic deposition (ELD), a well-suited method for the fabrication of films with controllable properties, at low processing temperature and cost. The CeCCs were deposited at room temperature from Ce(NO3)3 solution, applying different cathodic potentials (− 1.1, -1.4 and − 1.6 V vs. SCE) for different deposition times between 5 and 20 min. Structural, morphological and compositional properties of the films were characterized by X-ray diffraction, Raman spectroscopy and scanning electron microscopy coupled with energy dispersive spectroscopy. Ceria films were nanostructured, exhibiting a cubic fluorite structure. From corrosion perspective, the quality of CeCCs was evaluated in 0.5 M NaCl solution via electrochemical impedance spectroscopy and linear sweep voltammetry. As shown, the coating corrosion quality is the interplay between deposition potential and deposition time. The highest potential led to highly cracked films of poor adherence, even at the shortest deposition time, which disqualified them from any corrosion protection application. The lowest potential (− 1.1 V) produced crack-free coatings, but longer times (≥ 10 min) were needed to provide the protective layer formation. The best corrosion protection offered CeCCs prepared at − 1.4 V. The highest Rp (58.2 kΩ cm2) and the smallest CPE (12.6 · 10- 6sn Ω- 1 cm) were obtained at 20 min deposition time. However, from economical point of view, 10 min deposition is a promising choice. These CeCCs also improved pitting corrosion resistance owing to homogeneous microstructure and sufficient thickness.
Progress in Organic Coatings, 2009
ABSTRACT The electrochemical characteristics, adhesion and morphology of methacryloxypropyltrimet... more ABSTRACT The electrochemical characteristics, adhesion and morphology of methacryloxypropyltrimethoxysilane (MAPT) films on aluminium were investigated during exposure to 3 wt.% NaCl. The MAPT films were deposited on aluminium surface from 2 to 5 vol.% methacryloxypropyltrimethoxysilane solutions, with the aim to investigate the influence of deposition parameters (silane solution concentration and curing time) on electrochemical characteristics, adhesion and morphology of MAPT films on aluminium.Using electrochemical impedance spectroscopy (EIS), potential–time measurements, adhesion measurements and optical microscopy coupled with image analysis, it was shown that films deposited from 5 vol.% solution exhibited better corrosion stability and adhesion, as well as lower porosity comparing to 2 vol.% solution and improved the corrosion protection of aluminium substrate, while the curing time had no influence on these characteristics.
Progress in Organic Coatings, 1995
Cataphoretic deposition of an epoxy primer was carried out on four different substrates: bare ste... more Cataphoretic deposition of an epoxy primer was carried out on four different substrates: bare steel; phosphated steel; bare zinc-plated steel; and phosphated zinc-plated steel. Film growth was followed by observing the deposition current and local temperature throughout the deposition. The protective properties of the cured films at two different thicknesses formed on different substrates were observed by a.c. impedance measurements following exposure to 3% NaCl solution. It appears that the substrate affects the properties of the first-deposited layers of the coating. Models which explain the different properties of fihns formed on different substrates are given.
Progress in Organic Coatings, 2007
The adhesion and electrochemical properties of epoxy coatings electrodeposited on hot-dip galvani... more The adhesion and electrochemical properties of epoxy coatings electrodeposited on hot-dip galvanized steel with and without passive films were investigated during exposure to 3% NaCl. The passive films were formed in hot air, in boiling water and by chromating. Adhesion was measured both by a standardized pull-off method and by swelling in N-methyl pyrrolidone. Pretreatment of hot-dip galvanized steel with passive film formed in hot air increases both dry and wet adhesion strength of the epoxy coating compared to pretreatment with passive film formed in boiling water and chromate coating. The overall increase of wet adhesion for this sample was maintained throughout the whole investigated time period. It was shown that the change in adhesion of epoxy coating on a chromate coating is smallest of all investigated samples, although the initial value of adhesion on this surface had the lowest value. The corrosion stability of coated Zn samples pretreated by different methods, was investigated by electrochemical impedance spectroscopy and in the initial time of exposure to NaCl the highest values of pore resistance were also obtained for the epoxy coating on Zn pretreated in hot air, whereas the epoxy coating on a HDG steel with a chromate coating showed the smallest change in electrochemical properties (pore resistance, coating capacitance, charge-transfer resistance) during prolonged exposure time.
Progress in Organic Coatings, 2006
The corrosion behavior, sorption characteristics and thermal stability of epoxy coatings electrod... more The corrosion behavior, sorption characteristics and thermal stability of epoxy coatings electrodeposited on mild steel (MS) and mild steel with electrochemically deposited polyaniline (PANI) film were investigated in 3% NaCl solution using electrochemical impedance spectroscopy (EIS) and thermogravimetric analysis (TGA). Electrochemical deposition of PANI film on mild steel was performed from aqueous solution of 0.5 M sodium benzoate and 0.1 M aniline at constant current density of 1.5 mA cm −2. Epoxy coatings on mild steel and mild steel with PANI film were deposited at constant voltage. It was shown that during initial time of exposure to 3% NaCl, PANI/epoxy coating system on mild steel has lower values of pore resistance (obtained from EIS), greater amount of absorbed water and lower thermal stability (obtained from TGA) which indicate more porous structure comparing to epoxy coating on mild steel. During prolonged exposure to 3% NaCl, PANI/epoxy coating system exhibited increased corrosion protection of mild steel comparing to epoxy coating due to the barrier effect of PANI film and the influence of the dissolved molecular oxygen on cathodic and anodic reaction. Differences between corrosion behavior of epoxy coated and PANI/epoxy coated mild steel in acid and neutral solutions has been discussed.
Journal of the Serbian Chemical Society, 2002
The model of organic film growth on a cathode during electrodeposition process proposes the curre... more The model of organic film growth on a cathode during electrodeposition process proposes the current density-time and film thickness-time relationships and enables the evaluation of the rate contents for the electrochemical reaction of OH? ion evolution and for the chemical reaction of organic film deposition. The dependencies of film thickness and rate constants on the applied voltage, bath temperature and resin concentration in the electrodeposition bath have also been obtained. The deposition parameters have a great effect on the cathodic electrodeposition process and on the protective properties of the obtained electrodeposited coatings. From the time dependencies of the pore resistance, coating capacitance and relative permittivity, obtained from impedance measurements, the effect of applied voltage, bath temperature and resin concentration on the protective properties of electrodeposited coatings has been shown. Using electrochemical impedance spectroscopy, thermogravimetric an...
Journal of Materials Science: Materials in Medicine, 2011
Alginate colloid solution containing electrochemically synthesized silver nanoparticles (AgNPs) w... more Alginate colloid solution containing electrochemically synthesized silver nanoparticles (AgNPs) was investigated regarding the nanoparticle stabilization and possibilities for production of alginate based nanocomposite hydrogels in different forms. AgNPs were shown to continue to grow in alginate solutions for additional 3 days after the synthesis by aggregative mechanism and Ostwald ripening. Thereafter, the colloid solution remains stable for 30 days and could be used alone or in mixtures with aqueous solutions of poly(vinyl alcohol) (PVA) and poly(N-vinyl-2-pyrrolidone) (PVP) while preserving AgNPs as verified by UV-Vis spectroscopy studies. We have optimized techniques for production of Ag/alginate microbeads and Ag/alginate/PVA beads, which were shown to efficiently release AgNPs decreasing the Escherichia coli concentration in suspensions for 99.9% over 24 h. Furthermore, Ag/hydrogel discs based on alginate, PVA and PVP were produced by freezing-thawing technique allowing adjustments of hydrogel composition and mechanical properties as demonstrated in compression studies performed in a biomimetic bioreactor.
Corrosion Science, 2008
The electrochemical and transport properties and adhesion of epoxy coatings electrodeposited on a... more The electrochemical and transport properties and adhesion of epoxy coatings electrodeposited on aluminum pretreated by vinyltriethoxysilane (VTES) were investigated during exposure to 3% NaCl. The VTES films were deposited on aluminum surface from 2% and 5% vinyltriethoxysilane solution. The electrochemical results showed that the pretreatment based on VTES film deposited from 5% solution provides enhanced barrier properties and excellent corrosion protection. The values of diffusion coefficient of water through epoxy coating on this substrate and water content inside the epoxy coating were the smallest, indicating the low porosity of the coating. In addition, the good adhesion was maintained throughout the whole investigated time period.
Corrosion Science, 1996
Organic protective coatings on steel were formed by cathodic electrodeposition of an epoxy resin ... more Organic protective coatings on steel were formed by cathodic electrodeposition of an epoxy resin modified by an amine and isocyanate using a constant voltage method (resin concentration 10%wt, temperature 26 °C, applied voltage 250 V). The corrosion behaviour of these coatings was investigated during exposure to different corrosive agents (H2O, 3% NaCl, 3% Na2SO4, 3% sodium salt of 2-naphthol-3,6 disulphonic
Corrosion Science, 1995
A.C. impedance measurements carried out on epoxy-resin elcctrocoated steels were used to determin... more A.C. impedance measurements carried out on epoxy-resin elcctrocoated steels were used to determine the pore resistance of the organic film as a function of time of exposure to 3% sodium chloride solution. The thermogravimctric analysis of coatings after various exposure times enabled determination of the quantity of electrolyte inside the pores, while gravimetric liquid sorption experiments were used to evaluate
Corrosion Science, 1990
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Applied Surface Science, 2011
The influence of deposition temperature and concentration of NaNO 2 in the phosphating bath on th... more The influence of deposition temperature and concentration of NaNO 2 in the phosphating bath on the surface morphology and coverage of iron-phosphate coatings on low carbon steel was investigated. The phosphate coatings were chemically deposited on steel from phosphate bath at different temperatures (30-70 • C) and with the addition of different amounts of accelerator, NaNO 2 (0.1, 0.5 and 1.0 g dm −3). The morphology of phosphate coatings was investigated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The composition of iron-phosphate coatings was determined using energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). Surface coverage was evaluated by the voltammetric anodic dissolution (VAD) technique. It was shown that the increase in temperature of the NaNO 2-free phosphating bath up to 70 • C caused an increase in surface coverage. The addition of NaNO 2 in the phosphating bath significantly increased the surface coverage of phosphate coatings deposited at temperatures lower than 50 • C. The phosphate crystals were of laminated and needle-like structures for deposits obtained at temperatures lower than 50 • C, while at higher temperatures needle-like structure was transformed to laminated structure. The increase in NaNO 2 concentration in the phosphating bath from 0.1 to 1.0 g dm −3 did not significantly increase the surface coverage, but decreased the crystals size, consequently favouring the phosphate nucleation and better packing of the crystals.
Materials Science Forum, 1998
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Papers by Vesna Mišković-Stanković