TY  - JOUR
AU  - Obradović, Nina
AU  - Filipović, Suzana
AU  - Fahrenholtz, William G.
AU  - Marinković, Bojan A.
AU  - Rogan, Jelena
AU  - Lević, Steva
AU  - Đorđević, Antonije
AU  - Pavlović, Vladimir B.
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6467
AB  - Magnesium aluminate has the spinel structure along with good mechanical, chemical, and thermal properties. Magnesium aluminate has a wide range of applications including refractory ceramics, optically transparent ceramic windows, and armors. Its low dielectric permeability and low loss tangent enable its applications for integrated electronic devices, as well. In this paper, MgO and Al2O3 powders were mixed in a one-to-one molar ratio and calcined at temperatures ranging from 1500 to 1800°C to produce phase pure spinel. Thereafter, pellets were crushed and treated in a planetary ball mill for 60 min to obtain a fine powder. All powders were examined for phase composition, crystal structure, and morphology. The obtained results showed that by increasing the temperature, samples with higher density were synthesized. Milling for 1 h led to formation of larger particles, but finer powders after milling. XRPD and Raman spectroscopy showed disorder in the crystal structure after milling.
AB  - Магнезијум алуминат поседује структуру спинела и добра механичка, хемијска и термичка својства. Има широк спектар примене, укључујући рефракторну керамику, оружје и оптички транспарентна керамичка стакла. Ниска диелектрична пермеабилност и тангенс губитака пружају овој керамици примену и у електричним направама. У овом раду, прахови MgO и Al2O3 су помешани у моларном односу 1:1 и калцинисани на температурама између 1500°C и 1800°C да би се добио спинел. Након тога, узорци су смрвљени и механички активирани у млину током 60 минута да би се добио фини уситњен прах. Одређени су фазни састав, кристална структура и морфологија свих прахова. Резултати су показали да са порастом температуре расте и густина синтетисаних узорака. Млевење од 1 сата води ка формирању већих честица, али финијих прахова након млевења. XRPD и Раман спектроскопија указују на неуређену кристалну структуру након млевења.
PB  - International Institute for the Science of Sintering (IISS)
T2  - Science of Sintering
T1  - Morphological and Structural Characterization of MgAl2O4 Spinel
EP  - 10
IS  - 1
SP  - 1
VL  - 55
DO  - 10.2298/SOS2301001O
ER  - 

@article{
author = "Obradović, Nina and Filipović, Suzana and Fahrenholtz, William G. and Marinković, Bojan A. and Rogan, Jelena and Lević, Steva and Đorđević, Antonije and Pavlović, Vladimir B.",
year = "2023",
abstract = "Magnesium aluminate has the spinel structure along with good mechanical, chemical, and thermal properties. Magnesium aluminate has a wide range of applications including refractory ceramics, optically transparent ceramic windows, and armors. Its low dielectric permeability and low loss tangent enable its applications for integrated electronic devices, as well. In this paper, MgO and Al2O3 powders were mixed in a one-to-one molar ratio and calcined at temperatures ranging from 1500 to 1800°C to produce phase pure spinel. Thereafter, pellets were crushed and treated in a planetary ball mill for 60 min to obtain a fine powder. All powders were examined for phase composition, crystal structure, and morphology. The obtained results showed that by increasing the temperature, samples with higher density were synthesized. Milling for 1 h led to formation of larger particles, but finer powders after milling. XRPD and Raman spectroscopy showed disorder in the crystal structure after milling., Магнезијум алуминат поседује структуру спинела и добра механичка, хемијска и термичка својства. Има широк спектар примене, укључујући рефракторну керамику, оружје и оптички транспарентна керамичка стакла. Ниска диелектрична пермеабилност и тангенс губитака пружају овој керамици примену и у електричним направама. У овом раду, прахови MgO и Al2O3 су помешани у моларном односу 1:1 и калцинисани на температурама између 1500°C и 1800°C да би се добио спинел. Након тога, узорци су смрвљени и механички активирани у млину током 60 минута да би се добио фини уситњен прах. Одређени су фазни састав, кристална структура и морфологија свих прахова. Резултати су показали да са порастом температуре расте и густина синтетисаних узорака. Млевење од 1 сата води ка формирању већих честица, али финијих прахова након млевења. XRPD и Раман спектроскопија указују на неуређену кристалну структуру након млевења.",
publisher = "International Institute for the Science of Sintering (IISS)",
journal = "Science of Sintering",
title = "Morphological and Structural Characterization of MgAl2O4 Spinel",
pages = "10-1",
number = "1",
volume = "55",
doi = "10.2298/SOS2301001O"
}

Obradović, N., Filipović, S., Fahrenholtz, W. G., Marinković, B. A., Rogan, J., Lević, S., Đorđević, A.,& Pavlović, V. B.. (2023). Morphological and Structural Characterization of MgAl2O4 Spinel. in Science of Sintering
International Institute for the Science of Sintering (IISS)., 55(1), 1-10.
https://doi.org/10.2298/SOS2301001O

Obradović N, Filipović S, Fahrenholtz WG, Marinković BA, Rogan J, Lević S, Đorđević A, Pavlović VB. Morphological and Structural Characterization of MgAl2O4 Spinel. in Science of Sintering. 2023;55(1):1-10.
doi:10.2298/SOS2301001O .

Obradović, Nina, Filipović, Suzana, Fahrenholtz, William G., Marinković, Bojan A., Rogan, Jelena, Lević, Steva, Đorđević, Antonije, Pavlović, Vladimir B., "Morphological and Structural Characterization of MgAl2O4 Spinel" in Science of Sintering, 55, no. 1 (2023):1-10,
https://doi.org/10.2298/SOS2301001O . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Feng, Lun
AU  - Filipović, Suzana
AU  - Mirković, Miljana
AU  - Kosanović, Darko
AU  - Rogan, Jelena
AU  - Fahrenholtz, William G.
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6610
AB  - Zirconium carbide ceramics were prepared by carbothermal reduction of ZrO2 and C that were mixed by high-energy ball milling. Powders were milled for times from 0 to 120 min in air. As milling time increased, the surface area of the powders increased, indicating significant particle size reduction. Milled powders were reacted at 1600 °C and then densified by spark plasma sintering at 2000 °C, which was sufficient to convert the starting powders to zirconium carbide. Unmilled powders did not reach full density. Milled powders reached full density, but ZrO2 impurities were found for specimens prepared from powders milled for 60 and 120 min. Microstructure analysis showed that grain size was less than 2 µm for ceramics produced from powder milled for 15 min. Based on densification onset temperature and impurity levels, a milling time of 15 min gives the best balance of particle size reduction to promote densification while minimizing impurity levels.
PB  - Elsevier Ltd
T2  - Journal of the European Ceramic Society
T1  - Effect of mechanical activation on carbothermal synthesis and densification of ZrC
DO  - 10.1016/j.jeurceramsoc.2023.08.007
ER  - 

@article{
author = "Obradović, Nina and Feng, Lun and Filipović, Suzana and Mirković, Miljana and Kosanović, Darko and Rogan, Jelena and Fahrenholtz, William G.",
year = "2023",
abstract = "Zirconium carbide ceramics were prepared by carbothermal reduction of ZrO2 and C that were mixed by high-energy ball milling. Powders were milled for times from 0 to 120 min in air. As milling time increased, the surface area of the powders increased, indicating significant particle size reduction. Milled powders were reacted at 1600 °C and then densified by spark plasma sintering at 2000 °C, which was sufficient to convert the starting powders to zirconium carbide. Unmilled powders did not reach full density. Milled powders reached full density, but ZrO2 impurities were found for specimens prepared from powders milled for 60 and 120 min. Microstructure analysis showed that grain size was less than 2 µm for ceramics produced from powder milled for 15 min. Based on densification onset temperature and impurity levels, a milling time of 15 min gives the best balance of particle size reduction to promote densification while minimizing impurity levels.",
publisher = "Elsevier Ltd",
journal = "Journal of the European Ceramic Society",
title = "Effect of mechanical activation on carbothermal synthesis and densification of ZrC",
doi = "10.1016/j.jeurceramsoc.2023.08.007"
}

Obradović, N., Feng, L., Filipović, S., Mirković, M., Kosanović, D., Rogan, J.,& Fahrenholtz, W. G.. (2023). Effect of mechanical activation on carbothermal synthesis and densification of ZrC. in Journal of the European Ceramic Society
Elsevier Ltd..
https://doi.org/10.1016/j.jeurceramsoc.2023.08.007

Obradović N, Feng L, Filipović S, Mirković M, Kosanović D, Rogan J, Fahrenholtz WG. Effect of mechanical activation on carbothermal synthesis and densification of ZrC. in Journal of the European Ceramic Society. 2023;.
doi:10.1016/j.jeurceramsoc.2023.08.007 .

Obradović, Nina, Feng, Lun, Filipović, Suzana, Mirković, Miljana, Kosanović, Darko, Rogan, Jelena, Fahrenholtz, William G., "Effect of mechanical activation on carbothermal synthesis and densification of ZrC" in Journal of the European Ceramic Society (2023),
https://doi.org/10.1016/j.jeurceramsoc.2023.08.007 . .

TY  - JOUR
AU  - Popović, Mina
AU  - Veličković, Zlate S.
AU  - Bogdanov, Jovica
AU  - Marinković, Aleksandar D.
AU  - Luna, Mariano Casas
AU  - Trajković, Isaak
AU  - Obradović, Nina
AU  - Pavlović, Vladimir
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5106
AB  - In this study, the structure, morphology and composition of the synthesized magnetite/3D-printed wollastonite (3D_W/M) composite were characterized, and its adsorption performance with respect to As(V) and Cr(VI) were studied. Magnetite (MG) modified 3D printed wollastonite was obtained by two step procedure: modification of 3D_W with 3-aminoproylsilane (APTES) followed by controlled magnetite (MG) deposition to obtain 3D_W/M adsorbent. The structure/properties of 3D_W/M were confirmed by applying FTIR, XRD, TGD/DTA, and SEM analysis. The adsorption properties of hybrid adsorbents were carried out for As(V) and Cr(VI) removal-one relative to the initial pH value, the adsorbent mass, the temperature, and the adsorption time. Time-dependent adsorption study was best described by pseudo-second order equation, while Weber Morris analysis showed that intraparticle diffusion controled diffusional transport. Similar activation energy, 17.44 and 14.49 kJ•mol-1 for adsorption As(V) and Cr(VI) on 3D_W/M, respectively, indicated main contribution of physical adsorption. Determination of adsorption parameters was performed by applying different adsorption isotherm models, and the best fit was obtained using Freundlich model. The adsorption capacity of 24.16 and 29.6 mg g-1 for As(V) and Cr(VI) at 2o C, Co = 5.5 and 5.3 mg L-1, respectively, were obtained. Thermodynamic study indicated favourable process at a higher temperature. Preliminary fixed-bed column study and results fitting with Bohart-Adams, Yoon-Nelson, Thomas, and Modified dose-response model showed good agreement with results from the batch study.
PB  - International Institute for the Science of Sintering (IISS)
T2  - Science of Sintering
T1  - Removal of the As(V) and Cr(VI) from the Water Using Magnetite/3D-Printed Wollastonite Hybrid Adsorbent
EP  - 124
IS  - 1
SP  - 105
VL  - 54
DO  - 10.2298/SOS2201105P
ER  - 

@article{
author = "Popović, Mina and Veličković, Zlate S. and Bogdanov, Jovica and Marinković, Aleksandar D. and Luna, Mariano Casas and Trajković, Isaak and Obradović, Nina and Pavlović, Vladimir",
year = "2022",
abstract = "In this study, the structure, morphology and composition of the synthesized magnetite/3D-printed wollastonite (3D_W/M) composite were characterized, and its adsorption performance with respect to As(V) and Cr(VI) were studied. Magnetite (MG) modified 3D printed wollastonite was obtained by two step procedure: modification of 3D_W with 3-aminoproylsilane (APTES) followed by controlled magnetite (MG) deposition to obtain 3D_W/M adsorbent. The structure/properties of 3D_W/M were confirmed by applying FTIR, XRD, TGD/DTA, and SEM analysis. The adsorption properties of hybrid adsorbents were carried out for As(V) and Cr(VI) removal-one relative to the initial pH value, the adsorbent mass, the temperature, and the adsorption time. Time-dependent adsorption study was best described by pseudo-second order equation, while Weber Morris analysis showed that intraparticle diffusion controled diffusional transport. Similar activation energy, 17.44 and 14.49 kJ•mol-1 for adsorption As(V) and Cr(VI) on 3D_W/M, respectively, indicated main contribution of physical adsorption. Determination of adsorption parameters was performed by applying different adsorption isotherm models, and the best fit was obtained using Freundlich model. The adsorption capacity of 24.16 and 29.6 mg g-1 for As(V) and Cr(VI) at 2o C, Co = 5.5 and 5.3 mg L-1, respectively, were obtained. Thermodynamic study indicated favourable process at a higher temperature. Preliminary fixed-bed column study and results fitting with Bohart-Adams, Yoon-Nelson, Thomas, and Modified dose-response model showed good agreement with results from the batch study.",
publisher = "International Institute for the Science of Sintering (IISS)",
journal = "Science of Sintering",
title = "Removal of the As(V) and Cr(VI) from the Water Using Magnetite/3D-Printed Wollastonite Hybrid Adsorbent",
pages = "124-105",
number = "1",
volume = "54",
doi = "10.2298/SOS2201105P"
}

Popović, M., Veličković, Z. S., Bogdanov, J., Marinković, A. D., Luna, M. C., Trajković, I., Obradović, N.,& Pavlović, V.. (2022). Removal of the As(V) and Cr(VI) from the Water Using Magnetite/3D-Printed Wollastonite Hybrid Adsorbent. in Science of Sintering
International Institute for the Science of Sintering (IISS)., 54(1), 105-124.
https://doi.org/10.2298/SOS2201105P

Popović M, Veličković ZS, Bogdanov J, Marinković AD, Luna MC, Trajković I, Obradović N, Pavlović V. Removal of the As(V) and Cr(VI) from the Water Using Magnetite/3D-Printed Wollastonite Hybrid Adsorbent. in Science of Sintering. 2022;54(1):105-124.
doi:10.2298/SOS2201105P .

Popović, Mina, Veličković, Zlate S., Bogdanov, Jovica, Marinković, Aleksandar D., Luna, Mariano Casas, Trajković, Isaak, Obradović, Nina, Pavlović, Vladimir, "Removal of the As(V) and Cr(VI) from the Water Using Magnetite/3D-Printed Wollastonite Hybrid Adsorbent" in Science of Sintering, 54, no. 1 (2022):105-124,
https://doi.org/10.2298/SOS2201105P . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Rusmirović, Jelena
AU  - Filipović, Suzana
AU  - Kosanović, Darko
AU  - Marinković, Aleksandar
AU  - Radić, Danka
AU  - Pavlović, Vladimir
PY  - 2020
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4449
AB  - Industrial/technological growth is directly connected with environmental pollution, but its influence can be minimized through pollution abatement approaches such as the treatment of industrial wastewater. In this study, novel porous amine-functionalized silicate minerals, specifically, cordierite was investigated for the removal of toxic heavy metals from industrial wastewaters. Cordierite supports were synthesized by mixing MgO, Al2O3, and SiO2 powders in 2:2:5 molar ratios, and mechanically activated via ball milling in ethanol for 10, 40, or 80 min. Pellets were sintered by heating in air at 20 degrees C min(-1) to 1,350 degrees C, for 2 h. Porous supports were produced by coarsely crushing the sintered pellets and mixing the crushed and sieved cordierite powder with 20 wt.% of a pore-forming agent, either nanocellulose or yeast. The resulting pellets were sintered by heating at 5 degrees C min(-1) to 700 degrees C in air. The synthetic cordierite support was modified by treatment in poly-ethylenimine. Activated supports were then tested for the removal of Ni2+ and Cd2+ ions. The phase composition of the cordierite supports was analyzed by the X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy. Analysis of adsorption isotherms, kinetics, and thermodynamic parameters indicated that adsorption was a spontaneous, endothermic process with a maximum adsorption capacity of 36 mg g(-1) for Cd2+ and 43 mg g(-1) for Ni2+. This work has shed light on the mechanism of heavy metal removal from the aquatic medium using the novel hybrid functionalized cordierite-based ceramic.
PB  - Desalination Publ, Hopkinton
T2  - Desalination and Water Treatment
T1  - Porous cordierite-supported polyethyleneimine composites for nickel(II) and cadmium(II) ions removal
EP  - 296
SP  - 283
VL  - 192
DO  - 10.5004/dwt.2020.25736
ER  - 

@article{
author = "Obradović, Nina and Rusmirović, Jelena and Filipović, Suzana and Kosanović, Darko and Marinković, Aleksandar and Radić, Danka and Pavlović, Vladimir",
year = "2020",
abstract = "Industrial/technological growth is directly connected with environmental pollution, but its influence can be minimized through pollution abatement approaches such as the treatment of industrial wastewater. In this study, novel porous amine-functionalized silicate minerals, specifically, cordierite was investigated for the removal of toxic heavy metals from industrial wastewaters. Cordierite supports were synthesized by mixing MgO, Al2O3, and SiO2 powders in 2:2:5 molar ratios, and mechanically activated via ball milling in ethanol for 10, 40, or 80 min. Pellets were sintered by heating in air at 20 degrees C min(-1) to 1,350 degrees C, for 2 h. Porous supports were produced by coarsely crushing the sintered pellets and mixing the crushed and sieved cordierite powder with 20 wt.% of a pore-forming agent, either nanocellulose or yeast. The resulting pellets were sintered by heating at 5 degrees C min(-1) to 700 degrees C in air. The synthetic cordierite support was modified by treatment in poly-ethylenimine. Activated supports were then tested for the removal of Ni2+ and Cd2+ ions. The phase composition of the cordierite supports was analyzed by the X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy. Analysis of adsorption isotherms, kinetics, and thermodynamic parameters indicated that adsorption was a spontaneous, endothermic process with a maximum adsorption capacity of 36 mg g(-1) for Cd2+ and 43 mg g(-1) for Ni2+. This work has shed light on the mechanism of heavy metal removal from the aquatic medium using the novel hybrid functionalized cordierite-based ceramic.",
publisher = "Desalination Publ, Hopkinton",
journal = "Desalination and Water Treatment",
title = "Porous cordierite-supported polyethyleneimine composites for nickel(II) and cadmium(II) ions removal",
pages = "296-283",
volume = "192",
doi = "10.5004/dwt.2020.25736"
}

Obradović, N., Rusmirović, J., Filipović, S., Kosanović, D., Marinković, A., Radić, D.,& Pavlović, V.. (2020). Porous cordierite-supported polyethyleneimine composites for nickel(II) and cadmium(II) ions removal. in Desalination and Water Treatment
Desalination Publ, Hopkinton., 192, 283-296.
https://doi.org/10.5004/dwt.2020.25736

Obradović N, Rusmirović J, Filipović S, Kosanović D, Marinković A, Radić D, Pavlović V. Porous cordierite-supported polyethyleneimine composites for nickel(II) and cadmium(II) ions removal. in Desalination and Water Treatment. 2020;192:283-296.
doi:10.5004/dwt.2020.25736 .

Obradović, Nina, Rusmirović, Jelena, Filipović, Suzana, Kosanović, Darko, Marinković, Aleksandar, Radić, Danka, Pavlović, Vladimir, "Porous cordierite-supported polyethyleneimine composites for nickel(II) and cadmium(II) ions removal" in Desalination and Water Treatment, 192 (2020):283-296,
https://doi.org/10.5004/dwt.2020.25736 . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Filipović, Suzana
AU  - Kosanović, Darko
AU  - Dapčević, Aleksandra
AU  - Đorđević, Antonije
AU  - Balać, Igor
AU  - Pavlović, Vladimir B.
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4264
AB  - Magnesium aluminate, MgAl2O4 and other alumina-based spinels are ceramics with high hardness, high melting point and mechanical strenght. Spinels can also be used as dielectrics in microwave applications. The goal of this study was to examine the effects of mechanical activation and sintering temperatures on physico-chemical properties of spinel. MgAl2O4 was produced by solid state reaction between MgO and alpha-Al2O3. The starting powders were mixed by ball milling to homogenize without significant particle size reduction. Mechanical activation of mixed powders was performed in a high-energy planetary ball mill in air for 1 h. Powders were compacted at 300 MPa. Heat treatments were performed in air, at temperatures ranging from 1200 to 1600 degrees C with 2 h dwell time, to determine the amount of spinel formation as a function of temperature. Phase composition and microstructure of initial powders and heated samples were determined by means of X-ray diffraction, particle size analysis, and scanning electron microscopy. The influences of milling and consolidation parameters were studied by electrical measurements and mechanical characterization. The main conclusion of this study was that mechanical activation for 60 min initiated a mechano-chemical reaction, resulted in spinel formation at much lower temperatures than within non-activated powders, and indicated that final sintering stage started at much lower temperatures for activated powders. Changes in microstructure parameters, as a consequence of mechanical treatment and subsequent heating of investigated powder mixtures, strongly affect electrical and mechanical properties of the final ceramics.
PB  - Elsevier Sci Ltd, Oxford
T2  - Ceramics International
T1  - The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics
EP  - 12021
IS  - 9
SP  - 12015
VL  - 45
DO  - 10.1016/j.ceramint.2019.03.095
ER  - 

@article{
author = "Obradović, Nina and Fahrenholtz, William G. and Filipović, Suzana and Kosanović, Darko and Dapčević, Aleksandra and Đorđević, Antonije and Balać, Igor and Pavlović, Vladimir B.",
year = "2019",
abstract = "Magnesium aluminate, MgAl2O4 and other alumina-based spinels are ceramics with high hardness, high melting point and mechanical strenght. Spinels can also be used as dielectrics in microwave applications. The goal of this study was to examine the effects of mechanical activation and sintering temperatures on physico-chemical properties of spinel. MgAl2O4 was produced by solid state reaction between MgO and alpha-Al2O3. The starting powders were mixed by ball milling to homogenize without significant particle size reduction. Mechanical activation of mixed powders was performed in a high-energy planetary ball mill in air for 1 h. Powders were compacted at 300 MPa. Heat treatments were performed in air, at temperatures ranging from 1200 to 1600 degrees C with 2 h dwell time, to determine the amount of spinel formation as a function of temperature. Phase composition and microstructure of initial powders and heated samples were determined by means of X-ray diffraction, particle size analysis, and scanning electron microscopy. The influences of milling and consolidation parameters were studied by electrical measurements and mechanical characterization. The main conclusion of this study was that mechanical activation for 60 min initiated a mechano-chemical reaction, resulted in spinel formation at much lower temperatures than within non-activated powders, and indicated that final sintering stage started at much lower temperatures for activated powders. Changes in microstructure parameters, as a consequence of mechanical treatment and subsequent heating of investigated powder mixtures, strongly affect electrical and mechanical properties of the final ceramics.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Ceramics International",
title = "The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics",
pages = "12021-12015",
number = "9",
volume = "45",
doi = "10.1016/j.ceramint.2019.03.095"
}

Obradović, N., Fahrenholtz, W. G., Filipović, S., Kosanović, D., Dapčević, A., Đorđević, A., Balać, I.,& Pavlović, V. B.. (2019). The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics. in Ceramics International
Elsevier Sci Ltd, Oxford., 45(9), 12015-12021.
https://doi.org/10.1016/j.ceramint.2019.03.095

Obradović N, Fahrenholtz WG, Filipović S, Kosanović D, Dapčević A, Đorđević A, Balać I, Pavlović VB. The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics. in Ceramics International. 2019;45(9):12015-12021.
doi:10.1016/j.ceramint.2019.03.095 .

Obradović, Nina, Fahrenholtz, William G., Filipović, Suzana, Kosanović, Darko, Dapčević, Aleksandra, Đorđević, Antonije, Balać, Igor, Pavlović, Vladimir B., "The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics" in Ceramics International, 45, no. 9 (2019):12015-12021,
https://doi.org/10.1016/j.ceramint.2019.03.095 . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Filipović, Suzana
AU  - Corlett, Cole
AU  - Đorđević, Pavle
AU  - Rogan, Jelena
AU  - Vulić, Predrag
AU  - Buljak, Vladimir
AU  - Pavlović, Vladimir B.
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4136
AB  - Single phase MgAl2O4 was made from a one-to-one molar ratio of MgO and Al2O3 powders mixed using ball-milling. Mixtures of MgO and Al2O3 were subsequently treated in planetary ball mill for 30, 60, 90 and 120 minutes in air. The aim of this study was to examine phase composition, microstructure, and densification behavior of sintered specimens. After sintering in dilatometer at 1500 degrees C, the powder was converted to single phase MgAl2O4. The results show that mechanical activation improved the densification behavior of MgAl2O4 sintered specimens, and it reduced the onset temperature for sintering by approx. 100 degrees C. Based on dilatometer data, powders were subsequently densified at 1450 degrees C by hot pressing. Almost all specimens exhibited full density, while sample activated for 30 minutes showed the fastest densification rate.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Characterization of MgAl2O4 Sintered Ceramics
EP  - 376
IS  - 4
SP  - 363
VL  - 51
DO  - 10.2298/SOS1904363O
ER  - 

@article{
author = "Obradović, Nina and Fahrenholtz, William G. and Filipović, Suzana and Corlett, Cole and Đorđević, Pavle and Rogan, Jelena and Vulić, Predrag and Buljak, Vladimir and Pavlović, Vladimir B.",
year = "2019",
abstract = "Single phase MgAl2O4 was made from a one-to-one molar ratio of MgO and Al2O3 powders mixed using ball-milling. Mixtures of MgO and Al2O3 were subsequently treated in planetary ball mill for 30, 60, 90 and 120 minutes in air. The aim of this study was to examine phase composition, microstructure, and densification behavior of sintered specimens. After sintering in dilatometer at 1500 degrees C, the powder was converted to single phase MgAl2O4. The results show that mechanical activation improved the densification behavior of MgAl2O4 sintered specimens, and it reduced the onset temperature for sintering by approx. 100 degrees C. Based on dilatometer data, powders were subsequently densified at 1450 degrees C by hot pressing. Almost all specimens exhibited full density, while sample activated for 30 minutes showed the fastest densification rate.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Characterization of MgAl2O4 Sintered Ceramics",
pages = "376-363",
number = "4",
volume = "51",
doi = "10.2298/SOS1904363O"
}

Obradović, N., Fahrenholtz, W. G., Filipović, S., Corlett, C., Đorđević, P., Rogan, J., Vulić, P., Buljak, V.,& Pavlović, V. B.. (2019). Characterization of MgAl2O4 Sintered Ceramics. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 51(4), 363-376.
https://doi.org/10.2298/SOS1904363O

Obradović N, Fahrenholtz WG, Filipović S, Corlett C, Đorđević P, Rogan J, Vulić P, Buljak V, Pavlović VB. Characterization of MgAl2O4 Sintered Ceramics. in Science of Sintering. 2019;51(4):363-376.
doi:10.2298/SOS1904363O .

Obradović, Nina, Fahrenholtz, William G., Filipović, Suzana, Corlett, Cole, Đorđević, Pavle, Rogan, Jelena, Vulić, Predrag, Buljak, Vladimir, Pavlović, Vladimir B., "Characterization of MgAl2O4 Sintered Ceramics" in Science of Sintering, 51, no. 4 (2019):363-376,
https://doi.org/10.2298/SOS1904363O . .

TY  - JOUR
AU  - Rusmirović, Jelena
AU  - Obradović, Nina
AU  - Perendija, Jovana
AU  - Umićević, Ana
AU  - Kapidžić, Ana
AU  - Vlahović, Branislav
AU  - Pavlović, Vera P.
AU  - Marinković, Aleksandar
AU  - Pavlović, Vladimir B.
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4223
AB  - Iron oxide, in the form of magnetite (MG)-functionalized porous wollastonite (WL), was used as an adsorbent for heavy metal ions (cadmium and nickel) and oxyanions (chromate and phosphate) removal from water. The porous WL was synthesized from calcium carbonate and siloxane by controlled sintering process using low molecular weight submicrosized poly(methyl methacrylate) as a pore-forming agent. The precipitation of MG nanoparticles was carried out directly by a polyol-medium solvothermal method or via branched amino/carboxylic acid cross-linker by solvent/nonsolvent method producing WL/MG and WL--APS/MG adsorbents, respectively. The structure/properties of MG functionalized WL was confirmed by applying FTIR, Raman, XRD, Mossbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456mgg(-1) for WL--APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382mgg(-1) for Cd2+, Ni2+, phosphate, and chromate, respectively, were obtained using nonlinear Langmuir model fitting. Adsorption phenomena were analyzed using monolayer statistical physics model for single adsorption with one energy. Kinetic study showed exceptionally higher pseudo-second-order rate constants for WL--APS/MG, e.g., 1.17-13.4 times, with respect to WL/MG indicating importance of both WL surface modification and controllable precipitation of MG on WL--APS.
PB  - Springer Heidelberg, Heidelberg
T2  - Environmental Science and Pollution Research
T1  - Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal
EP  - 12398
IS  - 12
SP  - 12379
VL  - 26
DO  - 10.1007/s11356-019-04625-0
ER  - 

@article{
author = "Rusmirović, Jelena and Obradović, Nina and Perendija, Jovana and Umićević, Ana and Kapidžić, Ana and Vlahović, Branislav and Pavlović, Vera P. and Marinković, Aleksandar and Pavlović, Vladimir B.",
year = "2019",
abstract = "Iron oxide, in the form of magnetite (MG)-functionalized porous wollastonite (WL), was used as an adsorbent for heavy metal ions (cadmium and nickel) and oxyanions (chromate and phosphate) removal from water. The porous WL was synthesized from calcium carbonate and siloxane by controlled sintering process using low molecular weight submicrosized poly(methyl methacrylate) as a pore-forming agent. The precipitation of MG nanoparticles was carried out directly by a polyol-medium solvothermal method or via branched amino/carboxylic acid cross-linker by solvent/nonsolvent method producing WL/MG and WL--APS/MG adsorbents, respectively. The structure/properties of MG functionalized WL was confirmed by applying FTIR, Raman, XRD, Mossbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456mgg(-1) for WL--APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382mgg(-1) for Cd2+, Ni2+, phosphate, and chromate, respectively, were obtained using nonlinear Langmuir model fitting. Adsorption phenomena were analyzed using monolayer statistical physics model for single adsorption with one energy. Kinetic study showed exceptionally higher pseudo-second-order rate constants for WL--APS/MG, e.g., 1.17-13.4 times, with respect to WL/MG indicating importance of both WL surface modification and controllable precipitation of MG on WL--APS.",
publisher = "Springer Heidelberg, Heidelberg",
journal = "Environmental Science and Pollution Research",
title = "Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal",
pages = "12398-12379",
number = "12",
volume = "26",
doi = "10.1007/s11356-019-04625-0"
}

Rusmirović, J., Obradović, N., Perendija, J., Umićević, A., Kapidžić, A., Vlahović, B., Pavlović, V. P., Marinković, A.,& Pavlović, V. B.. (2019). Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal. in Environmental Science and Pollution Research
Springer Heidelberg, Heidelberg., 26(12), 12379-12398.
https://doi.org/10.1007/s11356-019-04625-0

Rusmirović J, Obradović N, Perendija J, Umićević A, Kapidžić A, Vlahović B, Pavlović VP, Marinković A, Pavlović VB. Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal. in Environmental Science and Pollution Research. 2019;26(12):12379-12398.
doi:10.1007/s11356-019-04625-0 .

Rusmirović, Jelena, Obradović, Nina, Perendija, Jovana, Umićević, Ana, Kapidžić, Ana, Vlahović, Branislav, Pavlović, Vera P., Marinković, Aleksandar, Pavlović, Vladimir B., "Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal" in Environmental Science and Pollution Research, 26, no. 12 (2019):12379-12398,
https://doi.org/10.1007/s11356-019-04625-0 . .

TY  - JOUR
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Marković, Smilja
AU  - Đorđević, Antonije
AU  - Balać, Igor
AU  - Dapčević, Aleksandra
AU  - Rogan, Jelena
AU  - Pavlović, Vladimir B.
PY  - 2018
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3909
AB  - Corundum (alpha-alumina) is a suiTab. material for usage in various industry fields owing to its chemical stability, electrical and mechanical features. It is known that properties of ceramics could be modified by addition of different oxides, as well as by changing the consolidation parameters. In this respect, alumina was doped with 1 wt.% of Cr2O3, Mn2O3 and NiO, followed by 1 hour of mechanical activation in a high-energy planetary ball mill. A sensitive dilatometer was used for sintering of powder mixtures up to 1400 degrees C and recording the obtained dilatation. The final density varied between cca. 1.9 and 3.3 g/cm(3). Microstructural changes were detected by SEM measurements. Changes in electrical permittivity and loss tangent were associated with the preparation conditions (types of additives, duration of mechanical activation). For a given mixture, the sintering increases the relative permittivity and decreases losses, exhibiting the optimal values of 8.32 and 0.027, respectively, for the sample activated 60 minutes and sintered, with the addition of MnO2. Mechanical measurements indicate significant differences in strength with the addition of different transition metal oxides. Samples with Mn and Ni, activated and sintered, with strength of 121 and 86 MPa, respectively, have a significantly higher tensile strength than the other tested samples, due to their more compact microstructures.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Physical Properties of Sintered Alumina Doped with Different Oxides
EP  - 419
IS  - 4
SP  - 409
VL  - 50
DO  - 10.2298/SOS1804409F
ER  - 

@article{
author = "Filipović, Suzana and Obradović, Nina and Marković, Smilja and Đorđević, Antonije and Balać, Igor and Dapčević, Aleksandra and Rogan, Jelena and Pavlović, Vladimir B.",
year = "2018",
abstract = "Corundum (alpha-alumina) is a suiTab. material for usage in various industry fields owing to its chemical stability, electrical and mechanical features. It is known that properties of ceramics could be modified by addition of different oxides, as well as by changing the consolidation parameters. In this respect, alumina was doped with 1 wt.% of Cr2O3, Mn2O3 and NiO, followed by 1 hour of mechanical activation in a high-energy planetary ball mill. A sensitive dilatometer was used for sintering of powder mixtures up to 1400 degrees C and recording the obtained dilatation. The final density varied between cca. 1.9 and 3.3 g/cm(3). Microstructural changes were detected by SEM measurements. Changes in electrical permittivity and loss tangent were associated with the preparation conditions (types of additives, duration of mechanical activation). For a given mixture, the sintering increases the relative permittivity and decreases losses, exhibiting the optimal values of 8.32 and 0.027, respectively, for the sample activated 60 minutes and sintered, with the addition of MnO2. Mechanical measurements indicate significant differences in strength with the addition of different transition metal oxides. Samples with Mn and Ni, activated and sintered, with strength of 121 and 86 MPa, respectively, have a significantly higher tensile strength than the other tested samples, due to their more compact microstructures.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Physical Properties of Sintered Alumina Doped with Different Oxides",
pages = "419-409",
number = "4",
volume = "50",
doi = "10.2298/SOS1804409F"
}

Filipović, S., Obradović, N., Marković, S., Đorđević, A., Balać, I., Dapčević, A., Rogan, J.,& Pavlović, V. B.. (2018). Physical Properties of Sintered Alumina Doped with Different Oxides. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 50(4), 409-419.
https://doi.org/10.2298/SOS1804409F

Filipović S, Obradović N, Marković S, Đorđević A, Balać I, Dapčević A, Rogan J, Pavlović VB. Physical Properties of Sintered Alumina Doped with Different Oxides. in Science of Sintering. 2018;50(4):409-419.
doi:10.2298/SOS1804409F .

Filipović, Suzana, Obradović, Nina, Marković, Smilja, Đorđević, Antonije, Balać, Igor, Dapčević, Aleksandra, Rogan, Jelena, Pavlović, Vladimir B., "Physical Properties of Sintered Alumina Doped with Different Oxides" in Science of Sintering, 50, no. 4 (2018):409-419,
https://doi.org/10.2298/SOS1804409F . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Filipović, Suzana
AU  - Marković, Smilja
AU  - Mitrić, Miodrag
AU  - Rusmirović, Jelena
AU  - Marinković, Aleksandar
AU  - Antić, Vesna
AU  - Pavlović, Vladimir B.
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3755
AB  - In this study, porous macro- and micro-cellular wollastonite-based ceramics was synthesized. A ceramic precursor, methylhydrocyclosiloxane, together with micro-sized CaCO3, was used as a starting material. After 20 min of ultrasound treatment, and calcination at 250 degrees C for 30 min, different pore-forming agents were added to the as-obtained powders. Differential thermal analysis was used to determine characteristic temperatures of processes occurring within powders during heating. Based on the obtained results, the sintering regime was set up. The prepared mixtures were pressed into pallets and sintered at 900 degrees C. During the sintering regime, porous wollastonite-based ceramics was obtained. The phase composition of the sintered samples, as well as the microstructures, were analyzed by using X-ray diffraction and SEM. A two-phase system was detected in all samples, CaSiO3 wollastonite and Ca2SiO4 larnite, and their ratio varied with each pore-forming agent. It was observed that the addition of different pore-forming agents resulted in significantly different microstructures. In a batch test, the influence of pH, the contact time and the initial ion concentration on the adsorption efficiency of As+5, Cr(+6)and phosphate ions on the synthesized adsorbents were studied. Time-dependent adsorption is best described by the pseudo-second-order kinetic model and the Weber-Morris model, which predict intra-particle diffusion as a rate-controlling step of the overall process. High adsorption capacities, 21.93, 23.88, and 27.29 mg g(-1), were obtained for the CaCO3-siloxane-nanocellulose sorbent, and similar/lower capacities were obtained for the CaCO3-siloxane-PMMA and CaCO3-siloxane-cotton wool adsorbents.
PB  - Elsevier Sci Ltd, Oxford
T2  - Ceramics International
T1  - Influence of different pore-forming agents on wollastonite microstructures and adsorption capacities
EP  - 7468
IS  - 10
SP  - 7461
VL  - 43
DO  - 10.1016/j.ceramint.2017.03.021
ER  - 

@article{
author = "Obradović, Nina and Filipović, Suzana and Marković, Smilja and Mitrić, Miodrag and Rusmirović, Jelena and Marinković, Aleksandar and Antić, Vesna and Pavlović, Vladimir B.",
year = "2017",
abstract = "In this study, porous macro- and micro-cellular wollastonite-based ceramics was synthesized. A ceramic precursor, methylhydrocyclosiloxane, together with micro-sized CaCO3, was used as a starting material. After 20 min of ultrasound treatment, and calcination at 250 degrees C for 30 min, different pore-forming agents were added to the as-obtained powders. Differential thermal analysis was used to determine characteristic temperatures of processes occurring within powders during heating. Based on the obtained results, the sintering regime was set up. The prepared mixtures were pressed into pallets and sintered at 900 degrees C. During the sintering regime, porous wollastonite-based ceramics was obtained. The phase composition of the sintered samples, as well as the microstructures, were analyzed by using X-ray diffraction and SEM. A two-phase system was detected in all samples, CaSiO3 wollastonite and Ca2SiO4 larnite, and their ratio varied with each pore-forming agent. It was observed that the addition of different pore-forming agents resulted in significantly different microstructures. In a batch test, the influence of pH, the contact time and the initial ion concentration on the adsorption efficiency of As+5, Cr(+6)and phosphate ions on the synthesized adsorbents were studied. Time-dependent adsorption is best described by the pseudo-second-order kinetic model and the Weber-Morris model, which predict intra-particle diffusion as a rate-controlling step of the overall process. High adsorption capacities, 21.93, 23.88, and 27.29 mg g(-1), were obtained for the CaCO3-siloxane-nanocellulose sorbent, and similar/lower capacities were obtained for the CaCO3-siloxane-PMMA and CaCO3-siloxane-cotton wool adsorbents.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Ceramics International",
title = "Influence of different pore-forming agents on wollastonite microstructures and adsorption capacities",
pages = "7468-7461",
number = "10",
volume = "43",
doi = "10.1016/j.ceramint.2017.03.021"
}

Obradović, N., Filipović, S., Marković, S., Mitrić, M., Rusmirović, J., Marinković, A., Antić, V.,& Pavlović, V. B.. (2017). Influence of different pore-forming agents on wollastonite microstructures and adsorption capacities. in Ceramics International
Elsevier Sci Ltd, Oxford., 43(10), 7461-7468.
https://doi.org/10.1016/j.ceramint.2017.03.021

Obradović N, Filipović S, Marković S, Mitrić M, Rusmirović J, Marinković A, Antić V, Pavlović VB. Influence of different pore-forming agents on wollastonite microstructures and adsorption capacities. in Ceramics International. 2017;43(10):7461-7468.
doi:10.1016/j.ceramint.2017.03.021 .

Obradović, Nina, Filipović, Suzana, Marković, Smilja, Mitrić, Miodrag, Rusmirović, Jelena, Marinković, Aleksandar, Antić, Vesna, Pavlović, Vladimir B., "Influence of different pore-forming agents on wollastonite microstructures and adsorption capacities" in Ceramics International, 43, no. 10 (2017):7461-7468,
https://doi.org/10.1016/j.ceramint.2017.03.021 . .

TY  - JOUR
AU  - Obradović, Nina
AU  - Filipović, Suzana
AU  - Rusmirović, Jelena
AU  - Postole, Georgeta
AU  - Marinković, Aleksandar
AU  - Radić, Danka
AU  - Rakić, Vesna M.
AU  - Pavlović, Vladimir B.
AU  - Auroux, Aline
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3627
AB  - In this paper, synthesis of porous wollastonite-based ceramics was reported. Ceramic precursor, methylhydrocyclosiloxane, together with micro-sized CaCO3, was used as starting material. After 20 min of ultrasound treatment, and calcination at 250 degrees C for 30 min, yeast as a pore-forming agent was added to the as-obtained powders. Sintering regime was set up based on the results obtained by differential thermal analysis. Prepared mixture was pressed into pallets and sintered at 900 degrees C for 1 h. After the sintering regime, porous wollastonite-based ceramics was obtained. The phase composition of the sintered samples as well as microstructures was analyzed by X-ray diffraction method and SEM. In a batch test, the influence of pH, contact time and initial ion concentration on adsorption efficiency of As+5, Cr+6, and phosphate ions on synthesized wollastonite-based ceramics were studied. Time-dependent adsorption was best described by pseudo-second-order kinetic model and Weber-Morris model that predicted intra-particle diffusion as a rate-controlling step of overall process. High adsorption capacities 39.97, 21.87, and 15.29 mgg(-1) were obtained for As+5, Cr+6, and phosphate ions, respectively.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Formation of Porous Wollastonite-based Ceramics after Sintering With Yeast as the Pore-forming Agent
EP  - 246
IS  - 3
SP  - 235
VL  - 49
DO  - 10.2298/SOS1703235O
ER  - 

@article{
author = "Obradović, Nina and Filipović, Suzana and Rusmirović, Jelena and Postole, Georgeta and Marinković, Aleksandar and Radić, Danka and Rakić, Vesna M. and Pavlović, Vladimir B. and Auroux, Aline",
year = "2017",
abstract = "In this paper, synthesis of porous wollastonite-based ceramics was reported. Ceramic precursor, methylhydrocyclosiloxane, together with micro-sized CaCO3, was used as starting material. After 20 min of ultrasound treatment, and calcination at 250 degrees C for 30 min, yeast as a pore-forming agent was added to the as-obtained powders. Sintering regime was set up based on the results obtained by differential thermal analysis. Prepared mixture was pressed into pallets and sintered at 900 degrees C for 1 h. After the sintering regime, porous wollastonite-based ceramics was obtained. The phase composition of the sintered samples as well as microstructures was analyzed by X-ray diffraction method and SEM. In a batch test, the influence of pH, contact time and initial ion concentration on adsorption efficiency of As+5, Cr+6, and phosphate ions on synthesized wollastonite-based ceramics were studied. Time-dependent adsorption was best described by pseudo-second-order kinetic model and Weber-Morris model that predicted intra-particle diffusion as a rate-controlling step of overall process. High adsorption capacities 39.97, 21.87, and 15.29 mgg(-1) were obtained for As+5, Cr+6, and phosphate ions, respectively.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Formation of Porous Wollastonite-based Ceramics after Sintering With Yeast as the Pore-forming Agent",
pages = "246-235",
number = "3",
volume = "49",
doi = "10.2298/SOS1703235O"
}

Obradović, N., Filipović, S., Rusmirović, J., Postole, G., Marinković, A., Radić, D., Rakić, V. M., Pavlović, V. B.,& Auroux, A.. (2017). Formation of Porous Wollastonite-based Ceramics after Sintering With Yeast as the Pore-forming Agent. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 49(3), 235-246.
https://doi.org/10.2298/SOS1703235O

Obradović N, Filipović S, Rusmirović J, Postole G, Marinković A, Radić D, Rakić VM, Pavlović VB, Auroux A. Formation of Porous Wollastonite-based Ceramics after Sintering With Yeast as the Pore-forming Agent. in Science of Sintering. 2017;49(3):235-246.
doi:10.2298/SOS1703235O .

Obradović, Nina, Filipović, Suzana, Rusmirović, Jelena, Postole, Georgeta, Marinković, Aleksandar, Radić, Danka, Rakić, Vesna M., Pavlović, Vladimir B., Auroux, Aline, "Formation of Porous Wollastonite-based Ceramics after Sintering With Yeast as the Pore-forming Agent" in Science of Sintering, 49, no. 3 (2017):235-246,
https://doi.org/10.2298/SOS1703235O . .

TY  - JOUR
AU  - Brković, Danijela V.
AU  - Pavlović, Vladimir B.
AU  - Pavlović, Vera P.
AU  - Obradović, Nina
AU  - Mitrić, Miodrag
AU  - Stevanović, Sanja
AU  - Vlahović, Branislav
AU  - Uskoković, Petar
AU  - Marinković, Aleksandar
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3550
AB  - The structural characteristics of polymer nanocomposites with functionalized multiwall carbon nanotubes (MWCNTs) in poly(methyl methacrylate) matrix have been studied in relation to nanofiller loading and surface functionality. Different functional groups have been covalently attached on the MWCNTs sidewalls in order to induce interfacial interactions at nanofiller/polymer interface, which resulted in an improved nanomechanical features. Structural properties of nanocomposites, studied with XRD and Raman analysis, indicated the most pronounced decrease in a degree of amorphousness for samples containing 0.5 and 1 wt% of MWCNTs functionalized with dapsone (dapson-MWCNT) and diethyl malonate (dem-MWCNT). SEM and TEM micrographs confirmed improved dispersibility of the MWCNTs modified with aromatic structure of dapsone inside PMMA matrix. A significant increase in a glass transition temperature of over 60 degrees C has been found for the 1 wt% dapson-MWCNT nanocomposite. Additional modification of dapson-MWCNT by further increasing aromaticity and voluminosity of attached moiety (fid-MWCNT), showed 30 degrees C increases in a glass transition temperature at 4 wt% of nanofiller loading, which is similar to shift of 37 degrees C with loading of MWCNTs modified with ester terminal group. A maximum increase of 56% of reduced modulus and 86% of hardness was obtained for 1 wt% loading of dapson-MWCNT nanofiller.
PB  - Wiley, Hoboken
T2  - Polymer Composites
T1  - Structural Properties of the Multiwall Carbon Nanotubes/Poly(Methyl Methacrylate) Nanocomposites: Effect of the Multiwall Carbon Nanotubes Covalent Functionalization
EP  - E489
SP  - E472
VL  - 38
DO  - 10.1002/pc.23996
ER  - 

@article{
author = "Brković, Danijela V. and Pavlović, Vladimir B. and Pavlović, Vera P. and Obradović, Nina and Mitrić, Miodrag and Stevanović, Sanja and Vlahović, Branislav and Uskoković, Petar and Marinković, Aleksandar",
year = "2017",
abstract = "The structural characteristics of polymer nanocomposites with functionalized multiwall carbon nanotubes (MWCNTs) in poly(methyl methacrylate) matrix have been studied in relation to nanofiller loading and surface functionality. Different functional groups have been covalently attached on the MWCNTs sidewalls in order to induce interfacial interactions at nanofiller/polymer interface, which resulted in an improved nanomechanical features. Structural properties of nanocomposites, studied with XRD and Raman analysis, indicated the most pronounced decrease in a degree of amorphousness for samples containing 0.5 and 1 wt% of MWCNTs functionalized with dapsone (dapson-MWCNT) and diethyl malonate (dem-MWCNT). SEM and TEM micrographs confirmed improved dispersibility of the MWCNTs modified with aromatic structure of dapsone inside PMMA matrix. A significant increase in a glass transition temperature of over 60 degrees C has been found for the 1 wt% dapson-MWCNT nanocomposite. Additional modification of dapson-MWCNT by further increasing aromaticity and voluminosity of attached moiety (fid-MWCNT), showed 30 degrees C increases in a glass transition temperature at 4 wt% of nanofiller loading, which is similar to shift of 37 degrees C with loading of MWCNTs modified with ester terminal group. A maximum increase of 56% of reduced modulus and 86% of hardness was obtained for 1 wt% loading of dapson-MWCNT nanofiller.",
publisher = "Wiley, Hoboken",
journal = "Polymer Composites",
title = "Structural Properties of the Multiwall Carbon Nanotubes/Poly(Methyl Methacrylate) Nanocomposites: Effect of the Multiwall Carbon Nanotubes Covalent Functionalization",
pages = "E489-E472",
volume = "38",
doi = "10.1002/pc.23996"
}

Brković, D. V., Pavlović, V. B., Pavlović, V. P., Obradović, N., Mitrić, M., Stevanović, S., Vlahović, B., Uskoković, P.,& Marinković, A.. (2017). Structural Properties of the Multiwall Carbon Nanotubes/Poly(Methyl Methacrylate) Nanocomposites: Effect of the Multiwall Carbon Nanotubes Covalent Functionalization. in Polymer Composites
Wiley, Hoboken., 38, E472-E489.
https://doi.org/10.1002/pc.23996

Brković DV, Pavlović VB, Pavlović VP, Obradović N, Mitrić M, Stevanović S, Vlahović B, Uskoković P, Marinković A. Structural Properties of the Multiwall Carbon Nanotubes/Poly(Methyl Methacrylate) Nanocomposites: Effect of the Multiwall Carbon Nanotubes Covalent Functionalization. in Polymer Composites. 2017;38:E472-E489.
doi:10.1002/pc.23996 .

Brković, Danijela V., Pavlović, Vladimir B., Pavlović, Vera P., Obradović, Nina, Mitrić, Miodrag, Stevanović, Sanja, Vlahović, Branislav, Uskoković, Petar, Marinković, Aleksandar, "Structural Properties of the Multiwall Carbon Nanotubes/Poly(Methyl Methacrylate) Nanocomposites: Effect of the Multiwall Carbon Nanotubes Covalent Functionalization" in Polymer Composites, 38 (2017):E472-E489,
https://doi.org/10.1002/pc.23996 . .

TY  - CONF
AU  - Vujančević, Jelena
AU  - Bjelajac, Anđelika
AU  - Obradović, Nina
AU  - Pavlović, Vera P.
AU  - Mitrić, Miodrag
AU  - Janaćković, Đorđe
AU  - Rašić, Goran
AU  - Vlahović, Branislav
AU  - Pavlović, Vladimir B.
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2864
AB  - The influence of electrochemical conditions and the heat treatment on the crystal structure and the microstructure evolution of TiO2 based nanotubes synthesized by the self-ordering anodization process is investigated in this work. The electrochemical anodization was performed at room temperature, for 30 minutes under 15, 20 and 25 V, with stirring. The as-anodized Ti foils were annealed in air at 450, 600, 650 and 700 °C for 30 minutes. The structure and the lattice dynamics of the samples has been studied by using XRD and Raman spectroscopy methods. The microstructure development of the 1-D TiO2 nanostructures has been analyzed by FESEM.
PB  - Belgrade : Serbian Ceramic Society
C3  - Advanced Ceramics and Application : new frontiers in multifunctional material science and processing
T1  - Influence of Synthesis Parameters on Structure of 1-D TiO2 nanostructures
EP  - 81
SP  - 81
UR  - https://hdl.handle.net/21.15107/rcub_vinar_7527
ER  - 

@conference{
author = "Vujančević, Jelena and Bjelajac, Anđelika and Obradović, Nina and Pavlović, Vera P. and Mitrić, Miodrag and Janaćković, Đorđe and Rašić, Goran and Vlahović, Branislav and Pavlović, Vladimir B.",
year = "2015",
abstract = "The influence of electrochemical conditions and the heat treatment on the crystal structure and the microstructure evolution of TiO2 based nanotubes synthesized by the self-ordering anodization process is investigated in this work. The electrochemical anodization was performed at room temperature, for 30 minutes under 15, 20 and 25 V, with stirring. The as-anodized Ti foils were annealed in air at 450, 600, 650 and 700 °C for 30 minutes. The structure and the lattice dynamics of the samples has been studied by using XRD and Raman spectroscopy methods. The microstructure development of the 1-D TiO2 nanostructures has been analyzed by FESEM.",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Advanced Ceramics and Application : new frontiers in multifunctional material science and processing",
title = "Influence of Synthesis Parameters on Structure of 1-D TiO2 nanostructures",
pages = "81-81",
url = "https://hdl.handle.net/21.15107/rcub_vinar_7527"
}

Vujančević, J., Bjelajac, A., Obradović, N., Pavlović, V. P., Mitrić, M., Janaćković, Đ., Rašić, G., Vlahović, B.,& Pavlović, V. B.. (2015). Influence of Synthesis Parameters on Structure of 1-D TiO2 nanostructures. in Advanced Ceramics and Application : new frontiers in multifunctional material science and processing
Belgrade : Serbian Ceramic Society., 81-81.
https://hdl.handle.net/21.15107/rcub_vinar_7527

Vujančević J, Bjelajac A, Obradović N, Pavlović VP, Mitrić M, Janaćković Đ, Rašić G, Vlahović B, Pavlović VB. Influence of Synthesis Parameters on Structure of 1-D TiO2 nanostructures. in Advanced Ceramics and Application : new frontiers in multifunctional material science and processing. 2015;:81-81.
https://hdl.handle.net/21.15107/rcub_vinar_7527 .

Vujančević, Jelena, Bjelajac, Anđelika, Obradović, Nina, Pavlović, Vera P., Mitrić, Miodrag, Janaćković, Đorđe, Rašić, Goran, Vlahović, Branislav, Pavlović, Vladimir B., "Influence of Synthesis Parameters on Structure of 1-D TiO2 nanostructures" in Advanced Ceramics and Application : new frontiers in multifunctional material science and processing (2015):81-81,
https://hdl.handle.net/21.15107/rcub_vinar_7527 .

TY  - JOUR
AU  - Lević, Steva
AU  - Obradović, Nina
AU  - Pavlović, Vladimir B.
AU  - Balanč, Bojana
AU  - Kostić, Ivana
AU  - Mitrić, Miodrag
AU  - Bugarski, Branko
AU  - Nedović, Viktor
PY  - 2014
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2745
AB  - In this study, polyvinyl alcohol (PVA) nanofibers with ethyl vanillin as an active compound were prepared using electrospinning technique. The final products of electrospinning process were in the form of nanofibers films. PVA/ethyl vanillin nanofibers, having fibers diameters in the range 100-1700 nm, were successfully electrospun from ethanol/water mixture of PVA and ethyl vanillin. The effects of immobilization process on ethyl vanillin thermal properties were investigated by differential scanning calorimetry (DSC). The results of DSC showed significant influence of immobilization process on thermal properties of ethyl vanillin. It was noticed that melting point of immobilized ethyl vanillin was lower (similar to 55 A degrees C) compared to free flavor (similar to 77 A degrees C). Our results showed that films based on PVA/ethyl vanillin nanofibers are mechanically stable.
PB  - Springer, Dordrecht
T2  - Journal of Thermal Analysis and Calorimetry
T1  - Thermal, morphological, and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process
EP  - 668
IS  - 2
SP  - 661
VL  - 118
DO  - 10.1007/s10973-014-4060-4
ER  - 

@article{
author = "Lević, Steva and Obradović, Nina and Pavlović, Vladimir B. and Balanč, Bojana and Kostić, Ivana and Mitrić, Miodrag and Bugarski, Branko and Nedović, Viktor",
year = "2014",
abstract = "In this study, polyvinyl alcohol (PVA) nanofibers with ethyl vanillin as an active compound were prepared using electrospinning technique. The final products of electrospinning process were in the form of nanofibers films. PVA/ethyl vanillin nanofibers, having fibers diameters in the range 100-1700 nm, were successfully electrospun from ethanol/water mixture of PVA and ethyl vanillin. The effects of immobilization process on ethyl vanillin thermal properties were investigated by differential scanning calorimetry (DSC). The results of DSC showed significant influence of immobilization process on thermal properties of ethyl vanillin. It was noticed that melting point of immobilized ethyl vanillin was lower (similar to 55 A degrees C) compared to free flavor (similar to 77 A degrees C). Our results showed that films based on PVA/ethyl vanillin nanofibers are mechanically stable.",
publisher = "Springer, Dordrecht",
journal = "Journal of Thermal Analysis and Calorimetry",
title = "Thermal, morphological, and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process",
pages = "668-661",
number = "2",
volume = "118",
doi = "10.1007/s10973-014-4060-4"
}

Lević, S., Obradović, N., Pavlović, V. B., Balanč, B., Kostić, I., Mitrić, M., Bugarski, B.,& Nedović, V.. (2014). Thermal, morphological, and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process. in Journal of Thermal Analysis and Calorimetry
Springer, Dordrecht., 118(2), 661-668.
https://doi.org/10.1007/s10973-014-4060-4

Lević S, Obradović N, Pavlović VB, Balanč B, Kostić I, Mitrić M, Bugarski B, Nedović V. Thermal, morphological, and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process. in Journal of Thermal Analysis and Calorimetry. 2014;118(2):661-668.
doi:10.1007/s10973-014-4060-4 .

Lević, Steva, Obradović, Nina, Pavlović, Vladimir B., Balanč, Bojana, Kostić, Ivana, Mitrić, Miodrag, Bugarski, Branko, Nedović, Viktor, "Thermal, morphological, and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process" in Journal of Thermal Analysis and Calorimetry, 118, no. 2 (2014):661-668,
https://doi.org/10.1007/s10973-014-4060-4 . .

TY  - CONF
AU  - Brković, Danijela V.
AU  - Pavlović, Vladimir B.
AU  - Pavlović, Vera P.
AU  - Obradović, Nina
AU  - Uskoković, Petar S.
AU  - Marinković, Aleksandar
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5207
AB  - In this study, we have performed functionalization of graphene nanoplatelets (GNPs) via Bingel reaction and investigated influence on the addition of covalently functionalized GPNs on the structural changes of the poly(methyl methacrylate). Preparation of poly(methyl methacrylate) nanocomposites with functionalized GNPs has been accomplished by drop casting method of dissolved PMMA mixed with modified graphene nanoplatelets dispersed in a N-methyl-1-pyrrolidone. Functionalizaton of graphene has been achieved under the conditions of Bingel reaction, which implies introduction of diethyl malonate on the graphene surfaces through the cyclopropane ring formation. Introduction of the cyclopropane ring on to the surface of graphene does not significantly affect the initial structural properties of graphene nanoplatelets, allowing better dispersible properties due to interaction of covalently attached diethyl malonate groups with the polymer chains. Fourier transform infrared spectroscopy (FTIR) and elemental analysis confirmed the effectiveness of the addition of diethyl malonate via Bingel reaction on the surface of GNPs. Scanning electron microscopy (SEM) has been used to provide information on the morphology of functionalized GNPs. Prepared nanocomposites have been characterized by Raman and FTIR spectroscopy. The changes regarding glass transition temperature have been monitored with differential scanning calorimetry (DSC).
PB  - Belgrade : Serbian Ceramic Society
C3  - Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts : II Serbian Ceramic Society Conference, Sep 30th-Oct 1st, 2013, Belgrade
T1  - Functionalization of graphene nanoplatelets via Bingel reaction for polymer nanocomposites
SP  - 49
UR  - https://hdl.handle.net/21.15107/rcub_dais_427
ER  - 

@conference{
author = "Brković, Danijela V. and Pavlović, Vladimir B. and Pavlović, Vera P. and Obradović, Nina and Uskoković, Petar S. and Marinković, Aleksandar",
year = "2013",
abstract = "In this study, we have performed functionalization of graphene nanoplatelets (GNPs) via Bingel reaction and investigated influence on the addition of covalently functionalized GPNs on the structural changes of the poly(methyl methacrylate). Preparation of poly(methyl methacrylate) nanocomposites with functionalized GNPs has been accomplished by drop casting method of dissolved PMMA mixed with modified graphene nanoplatelets dispersed in a N-methyl-1-pyrrolidone. Functionalizaton of graphene has been achieved under the conditions of Bingel reaction, which implies introduction of diethyl malonate on the graphene surfaces through the cyclopropane ring formation. Introduction of the cyclopropane ring on to the surface of graphene does not significantly affect the initial structural properties of graphene nanoplatelets, allowing better dispersible properties due to interaction of covalently attached diethyl malonate groups with the polymer chains. Fourier transform infrared spectroscopy (FTIR) and elemental analysis confirmed the effectiveness of the addition of diethyl malonate via Bingel reaction on the surface of GNPs. Scanning electron microscopy (SEM) has been used to provide information on the morphology of functionalized GNPs. Prepared nanocomposites have been characterized by Raman and FTIR spectroscopy. The changes regarding glass transition temperature have been monitored with differential scanning calorimetry (DSC).",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts : II Serbian Ceramic Society Conference, Sep 30th-Oct 1st, 2013, Belgrade",
title = "Functionalization of graphene nanoplatelets via Bingel reaction for polymer nanocomposites",
pages = "49",
url = "https://hdl.handle.net/21.15107/rcub_dais_427"
}

Brković, D. V., Pavlović, V. B., Pavlović, V. P., Obradović, N., Uskoković, P. S.,& Marinković, A.. (2013). Functionalization of graphene nanoplatelets via Bingel reaction for polymer nanocomposites. in Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts : II Serbian Ceramic Society Conference, Sep 30th-Oct 1st, 2013, Belgrade
Belgrade : Serbian Ceramic Society., 49.
https://hdl.handle.net/21.15107/rcub_dais_427

Brković DV, Pavlović VB, Pavlović VP, Obradović N, Uskoković PS, Marinković A. Functionalization of graphene nanoplatelets via Bingel reaction for polymer nanocomposites. in Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts : II Serbian Ceramic Society Conference, Sep 30th-Oct 1st, 2013, Belgrade. 2013;:49.
https://hdl.handle.net/21.15107/rcub_dais_427 .

Brković, Danijela V., Pavlović, Vladimir B., Pavlović, Vera P., Obradović, Nina, Uskoković, Petar S., Marinković, Aleksandar, "Functionalization of graphene nanoplatelets via Bingel reaction for polymer nanocomposites" in Advanced Ceramics and Application : new frontiers in multifunctional material science and processing : program and the book of abstracts : II Serbian Ceramic Society Conference, Sep 30th-Oct 1st, 2013, Belgrade (2013):49,
https://hdl.handle.net/21.15107/rcub_dais_427 .

TY  - CONF
AU  - Lević, Steva
AU  - Obradović, Nina
AU  - Pavlović, Vladimir B.
AU  - Isailović, Bojana
AU  - Kostić, Ivana
AU  - Bugarski, Branko
AU  - Nedović, Viktor
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2283
AB  - In this study, polyvinyl alcohol (PVA) nanofibers with ethyl vanillin as active compound were prepared using electrospinning technique. The final products of electrospinning process were in the form of films consist of nanofibers. PVNethyl vanillin nanofibers, having fibers diameters in the range 100-1700 nm, were successfully electrospun from ethanol/water mixture of PVA and ethyl vanillin. The effects of immobilization process on ethyl vanillin thermal properties were investigated by differential scanning calorimetry (DSC). The results of DSC showed significant influence of immobilization process on thermal properties of ethyl vanillin. It was noticed that melting point of immobilized ethyl vanillin was lower (~55°C) compared to free flavor (~77°C). Our results showed that films based on PVNethyl vanillin nanofibers are mechanically stable.
PB  - Vilnus : Central and Eastern European Committee for Thermal Analysis and Calorimetry
C3  - 2nd Central and Eastern European Conference on Thermal Analysis and Calorimetry 27-30 August 2013, V
T1  - Thermal, morphological and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process
EP  - 294
SP  - 294
UR  - https://hdl.handle.net/21.15107/rcub_technorep_2283
ER  - 

@conference{
author = "Lević, Steva and Obradović, Nina and Pavlović, Vladimir B. and Isailović, Bojana and Kostić, Ivana and Bugarski, Branko and Nedović, Viktor",
year = "2013",
abstract = "In this study, polyvinyl alcohol (PVA) nanofibers with ethyl vanillin as active compound were prepared using electrospinning technique. The final products of electrospinning process were in the form of films consist of nanofibers. PVNethyl vanillin nanofibers, having fibers diameters in the range 100-1700 nm, were successfully electrospun from ethanol/water mixture of PVA and ethyl vanillin. The effects of immobilization process on ethyl vanillin thermal properties were investigated by differential scanning calorimetry (DSC). The results of DSC showed significant influence of immobilization process on thermal properties of ethyl vanillin. It was noticed that melting point of immobilized ethyl vanillin was lower (~55°C) compared to free flavor (~77°C). Our results showed that films based on PVNethyl vanillin nanofibers are mechanically stable.",
publisher = "Vilnus : Central and Eastern European Committee for Thermal Analysis and Calorimetry",
journal = "2nd Central and Eastern European Conference on Thermal Analysis and Calorimetry 27-30 August 2013, V",
title = "Thermal, morphological and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process",
pages = "294-294",
url = "https://hdl.handle.net/21.15107/rcub_technorep_2283"
}

Lević, S., Obradović, N., Pavlović, V. B., Isailović, B., Kostić, I., Bugarski, B.,& Nedović, V.. (2013). Thermal, morphological and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process. in 2nd Central and Eastern European Conference on Thermal Analysis and Calorimetry 27-30 August 2013, V
Vilnus : Central and Eastern European Committee for Thermal Analysis and Calorimetry., 294-294.
https://hdl.handle.net/21.15107/rcub_technorep_2283

Lević S, Obradović N, Pavlović VB, Isailović B, Kostić I, Bugarski B, Nedović V. Thermal, morphological and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process. in 2nd Central and Eastern European Conference on Thermal Analysis and Calorimetry 27-30 August 2013, V. 2013;:294-294.
https://hdl.handle.net/21.15107/rcub_technorep_2283 .

Lević, Steva, Obradović, Nina, Pavlović, Vladimir B., Isailović, Bojana, Kostić, Ivana, Bugarski, Branko, Nedović, Viktor, "Thermal, morphological and mechanical properties of ethyl vanillin immobilized in polyvinyl alcohol by electrospinning process" in 2nd Central and Eastern European Conference on Thermal Analysis and Calorimetry 27-30 August 2013, V (2013):294-294,
https://hdl.handle.net/21.15107/rcub_technorep_2283 .