TY  - JOUR
AU  - Peles, A.
AU  - Aleksić, O.
AU  - Pavlović, Vera P.
AU  - Djoković, Vladimir
AU  - Dojčilović, Radovan
AU  - Nikolić, Z.
AU  - Marinković, F.
AU  - Mitrić, M.
AU  - Blagojević, Vladimir A.
AU  - Vlahović, Branislav
AU  - Pavlović, Vladimir
PY  - 2018
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4658
AB  - The influence of the mechanical activation of ZnO nanoparticle fillers on the structural and electrical properties of the matrix of poly(vinylidenefluoride)-ZnO (PVDF-ZnO) films was investigated. Transmission electron microscopy and scanning electron microscopy analyses showed that mechanical activation in a high energy planetary ball mill reduces the size of ZnO particles. X-ray diffraction and Raman spectroscopy revealed that PVDF crystallized predominantly as the gamma-phase. Non-activated ZnO filler reduces the degree of the crystallinity of the matrix and promotes crystallization of alpha-phase of PVDF in the film, while the fillers activated for 5 and 10 min induce crystallization of beta-phase, indicating that mechanical activation of the filler can be used as a general method for fabrication of PVDF composites with increased content of piezoelectric beta-phase crystals. Dielectric spectroscopy measurements show that polymer composite with the high content of beta-phase (with ZnO filler activated for 5 min) exhibits the highest value of dielectric permittivity in 150-400 K range of temperatures. Kinetic analysis shows combined effects of increased surface area and increased concentration of surface defects on the interactions between polymer chains and activated nanoparticles.
PB  - IOP Publishing Ltd, Bristol
T2  - Physica Scripta
T1  - Structural and electrical properties of ferroelectric poly(vinylidene fluoride) and mechanically activated ZnO nanoparticle composite films
IS  - 10
VL  - 93
DO  - 10.1088/1402-4896/aad749
ER  - 

@article{
author = "Peles, A. and Aleksić, O. and Pavlović, Vera P. and Djoković, Vladimir and Dojčilović, Radovan and Nikolić, Z. and Marinković, F. and Mitrić, M. and Blagojević, Vladimir A. and Vlahović, Branislav and Pavlović, Vladimir",
year = "2018",
abstract = "The influence of the mechanical activation of ZnO nanoparticle fillers on the structural and electrical properties of the matrix of poly(vinylidenefluoride)-ZnO (PVDF-ZnO) films was investigated. Transmission electron microscopy and scanning electron microscopy analyses showed that mechanical activation in a high energy planetary ball mill reduces the size of ZnO particles. X-ray diffraction and Raman spectroscopy revealed that PVDF crystallized predominantly as the gamma-phase. Non-activated ZnO filler reduces the degree of the crystallinity of the matrix and promotes crystallization of alpha-phase of PVDF in the film, while the fillers activated for 5 and 10 min induce crystallization of beta-phase, indicating that mechanical activation of the filler can be used as a general method for fabrication of PVDF composites with increased content of piezoelectric beta-phase crystals. Dielectric spectroscopy measurements show that polymer composite with the high content of beta-phase (with ZnO filler activated for 5 min) exhibits the highest value of dielectric permittivity in 150-400 K range of temperatures. Kinetic analysis shows combined effects of increased surface area and increased concentration of surface defects on the interactions between polymer chains and activated nanoparticles.",
publisher = "IOP Publishing Ltd, Bristol",
journal = "Physica Scripta",
title = "Structural and electrical properties of ferroelectric poly(vinylidene fluoride) and mechanically activated ZnO nanoparticle composite films",
number = "10",
volume = "93",
doi = "10.1088/1402-4896/aad749"
}

Peles, A., Aleksić, O., Pavlović, V. P., Djoković, V., Dojčilović, R., Nikolić, Z., Marinković, F., Mitrić, M., Blagojević, V. A., Vlahović, B.,& Pavlović, V.. (2018). Structural and electrical properties of ferroelectric poly(vinylidene fluoride) and mechanically activated ZnO nanoparticle composite films. in Physica Scripta
IOP Publishing Ltd, Bristol., 93(10).
https://doi.org/10.1088/1402-4896/aad749

Peles A, Aleksić O, Pavlović VP, Djoković V, Dojčilović R, Nikolić Z, Marinković F, Mitrić M, Blagojević VA, Vlahović B, Pavlović V. Structural and electrical properties of ferroelectric poly(vinylidene fluoride) and mechanically activated ZnO nanoparticle composite films. in Physica Scripta. 2018;93(10).
doi:10.1088/1402-4896/aad749 .

Peles, A., Aleksić, O., Pavlović, Vera P., Djoković, Vladimir, Dojčilović, Radovan, Nikolić, Z., Marinković, F., Mitrić, M., Blagojević, Vladimir A., Vlahović, Branislav, Pavlović, Vladimir, "Structural and electrical properties of ferroelectric poly(vinylidene fluoride) and mechanically activated ZnO nanoparticle composite films" in Physica Scripta, 93, no. 10 (2018),
https://doi.org/10.1088/1402-4896/aad749 . .

TY  - JOUR
AU  - Peles, A.
AU  - Pavlović, Vera P.
AU  - Filipović, Suzana
AU  - Obradović, N.
AU  - Mancić, L.
AU  - Krstić, J.
AU  - Mitrić, M.
AU  - Vlahović, Branislav
AU  - Rasić, G.
AU  - Kosanović, Darko
AU  - Pavlović, Vladimir
PY  - 2015
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3691
AB  - Commercially available ZnO powder was mechanically activated in a planetary ball mill. In order to investigate the specific surface area, pore volume and microstructure of non-activated and mechanically activated ZnO powders the authors performed N-2 physisorption, SEM and TEM. Crystallite size and lattice microstrain were analyzed by X-ray diffraction method. XRD patterns indicate that peak intensities are getting lower and expend with activation time. The reduction in crystallite size and increasing of lattice microstrain with prolonged milling time were determined applying the Rietveld's method. The difference between non-activated and the activated powder has been also observed by X-ray photoelectron spectroscopy (XPS). XPS is used for investigating the chemical bonding of ZnO powder by analyzing the energy of photoelectrons. The lattice vibration spectra were obtained using Raman spectroscopy. In Raman spectra some changes along with atypical resonant scattering were noticed, which were caused by mechanical activation.
PB  - Elsevier Science Sa, Lausanne
T2  - Journal of Alloys and Compounds
T1  - Structural investigation of mechanically activated ZnO powder
EP  - 979
SP  - 971
VL  - 648
DO  - 10.1016/j.jallcom.2015.06.247
ER  - 

@article{
author = "Peles, A. and Pavlović, Vera P. and Filipović, Suzana and Obradović, N. and Mancić, L. and Krstić, J. and Mitrić, M. and Vlahović, Branislav and Rasić, G. and Kosanović, Darko and Pavlović, Vladimir",
year = "2015",
abstract = "Commercially available ZnO powder was mechanically activated in a planetary ball mill. In order to investigate the specific surface area, pore volume and microstructure of non-activated and mechanically activated ZnO powders the authors performed N-2 physisorption, SEM and TEM. Crystallite size and lattice microstrain were analyzed by X-ray diffraction method. XRD patterns indicate that peak intensities are getting lower and expend with activation time. The reduction in crystallite size and increasing of lattice microstrain with prolonged milling time were determined applying the Rietveld's method. The difference between non-activated and the activated powder has been also observed by X-ray photoelectron spectroscopy (XPS). XPS is used for investigating the chemical bonding of ZnO powder by analyzing the energy of photoelectrons. The lattice vibration spectra were obtained using Raman spectroscopy. In Raman spectra some changes along with atypical resonant scattering were noticed, which were caused by mechanical activation.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Journal of Alloys and Compounds",
title = "Structural investigation of mechanically activated ZnO powder",
pages = "979-971",
volume = "648",
doi = "10.1016/j.jallcom.2015.06.247"
}

Peles, A., Pavlović, V. P., Filipović, S., Obradović, N., Mancić, L., Krstić, J., Mitrić, M., Vlahović, B., Rasić, G., Kosanović, D.,& Pavlović, V.. (2015). Structural investigation of mechanically activated ZnO powder. in Journal of Alloys and Compounds
Elsevier Science Sa, Lausanne., 648, 971-979.
https://doi.org/10.1016/j.jallcom.2015.06.247

Peles A, Pavlović VP, Filipović S, Obradović N, Mancić L, Krstić J, Mitrić M, Vlahović B, Rasić G, Kosanović D, Pavlović V. Structural investigation of mechanically activated ZnO powder. in Journal of Alloys and Compounds. 2015;648:971-979.
doi:10.1016/j.jallcom.2015.06.247 .

Peles, A., Pavlović, Vera P., Filipović, Suzana, Obradović, N., Mancić, L., Krstić, J., Mitrić, M., Vlahović, Branislav, Rasić, G., Kosanović, Darko, Pavlović, Vladimir, "Structural investigation of mechanically activated ZnO powder" in Journal of Alloys and Compounds, 648 (2015):971-979,
https://doi.org/10.1016/j.jallcom.2015.06.247 . .

TY  - JOUR
AU  - Obradović, N.
AU  - Djordjević, N.
AU  - Peles, A.
AU  - Filipović, Suzana
AU  - Mitrić, M.
AU  - Pavlović, Vladimir
PY  - 2015
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3786
AB  - Due to its characteristics, cordierite, 2MgO center dot 2Al(2)O(3)center dot 5SiO(2), is a high-temperature ceramic material of a great scientific interest. Mechanical activation of the starting mixtures containing 5.00 mass% TiO2 was performed in a high-energy ball mill for 10 minutes. The compaction pressure varied from 0.5 to 6tcm(-2) (49-588 MPa). The sintering process was performed at 1350 degrees C for four hours in the air atmosphere. The phase composition of the activated and sintered samples was analyzed using X-ray diffraction. Scanning electron microscopy was used to analyze the microstructure of both compacted and sintered samples. The authors have investigated the influence of compaction pressure on the sintered samples and their electrical properties.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - The Influence of Compaction Pressure on the Density and Electrical Properties of Cordierite-based Ceramics
EP  - 22
IS  - 1
SP  - 15
VL  - 47
DO  - 10.2298/SOS1501015O
ER  - 

@article{
author = "Obradović, N. and Djordjević, N. and Peles, A. and Filipović, Suzana and Mitrić, M. and Pavlović, Vladimir",
year = "2015",
abstract = "Due to its characteristics, cordierite, 2MgO center dot 2Al(2)O(3)center dot 5SiO(2), is a high-temperature ceramic material of a great scientific interest. Mechanical activation of the starting mixtures containing 5.00 mass% TiO2 was performed in a high-energy ball mill for 10 minutes. The compaction pressure varied from 0.5 to 6tcm(-2) (49-588 MPa). The sintering process was performed at 1350 degrees C for four hours in the air atmosphere. The phase composition of the activated and sintered samples was analyzed using X-ray diffraction. Scanning electron microscopy was used to analyze the microstructure of both compacted and sintered samples. The authors have investigated the influence of compaction pressure on the sintered samples and their electrical properties.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "The Influence of Compaction Pressure on the Density and Electrical Properties of Cordierite-based Ceramics",
pages = "22-15",
number = "1",
volume = "47",
doi = "10.2298/SOS1501015O"
}

Obradović, N., Djordjević, N., Peles, A., Filipović, S., Mitrić, M.,& Pavlović, V.. (2015). The Influence of Compaction Pressure on the Density and Electrical Properties of Cordierite-based Ceramics. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 47(1), 15-22.
https://doi.org/10.2298/SOS1501015O

Obradović N, Djordjević N, Peles A, Filipović S, Mitrić M, Pavlović V. The Influence of Compaction Pressure on the Density and Electrical Properties of Cordierite-based Ceramics. in Science of Sintering. 2015;47(1):15-22.
doi:10.2298/SOS1501015O .

Obradović, N., Djordjević, N., Peles, A., Filipović, Suzana, Mitrić, M., Pavlović, Vladimir, "The Influence of Compaction Pressure on the Density and Electrical Properties of Cordierite-based Ceramics" in Science of Sintering, 47, no. 1 (2015):15-22,
https://doi.org/10.2298/SOS1501015O . .

TY  - JOUR
AU  - Kosanović, Darko
AU  - Zivojinović, J.
AU  - Obradović, N.
AU  - Pavlović, Vera P.
AU  - Pavlović, Vladimir
AU  - Peles, A.
AU  - Ristić, M.M.
PY  - 2014
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3418
AB  - Ferroelectric barium strontium titanate (Ba0.77Sr0.23TiO3), BST, was prepared by solid-state reactions using as the starting compounds powder of barium carbonate (BaCO3), strontium carbonate (SrCO3) and titanium dioxide (TiO2 anatase). Non-activated mixtures and mixtures mechanically activated in a high-energy planetary ball mill (0, 5, 10, 20, 40, 80 and 120 min) were sintered at 1100, 1200, 1300 and 1400 degrees C for 2 h in air atmosphere. Defects and the effect of the beginning of the sintering process on the microstructure were investigated by scanning electron microscopy (SEM). Electrical measurements (loss tangent and resistivity as the function of frequency X-C =f(log nu)) were performed for ceramics sintered at 1400 degrees C for 2 h. It has been found that mechanical activation can reduce the sintering temperature by around 100 degrees C, which leads to significant energy savings. Furthermore, activated for 80 min and sintered at. 1400 degrees C for 2 h exhibit the largest density values and have about 36% lower dielectric loss at a frequency of 1 kHz and about 57% at a frequency of 10 kHz than the samples obtained from the initial non-activated powder sintered under the same conditions.
PB  - Elsevier Sci Ltd, Oxford
T2  - Ceramics International
T1  - The influence of mechanical activation on the electrical properties of Ba0.77Sr0.23TiO3 ceramics
EP  - 11888
IS  - 8
SP  - 11883
VL  - 40
DO  - 10.1016/j.ceramint.2014.04.023
ER  - 

@article{
author = "Kosanović, Darko and Zivojinović, J. and Obradović, N. and Pavlović, Vera P. and Pavlović, Vladimir and Peles, A. and Ristić, M.M.",
year = "2014",
abstract = "Ferroelectric barium strontium titanate (Ba0.77Sr0.23TiO3), BST, was prepared by solid-state reactions using as the starting compounds powder of barium carbonate (BaCO3), strontium carbonate (SrCO3) and titanium dioxide (TiO2 anatase). Non-activated mixtures and mixtures mechanically activated in a high-energy planetary ball mill (0, 5, 10, 20, 40, 80 and 120 min) were sintered at 1100, 1200, 1300 and 1400 degrees C for 2 h in air atmosphere. Defects and the effect of the beginning of the sintering process on the microstructure were investigated by scanning electron microscopy (SEM). Electrical measurements (loss tangent and resistivity as the function of frequency X-C =f(log nu)) were performed for ceramics sintered at 1400 degrees C for 2 h. It has been found that mechanical activation can reduce the sintering temperature by around 100 degrees C, which leads to significant energy savings. Furthermore, activated for 80 min and sintered at. 1400 degrees C for 2 h exhibit the largest density values and have about 36% lower dielectric loss at a frequency of 1 kHz and about 57% at a frequency of 10 kHz than the samples obtained from the initial non-activated powder sintered under the same conditions.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Ceramics International",
title = "The influence of mechanical activation on the electrical properties of Ba0.77Sr0.23TiO3 ceramics",
pages = "11888-11883",
number = "8",
volume = "40",
doi = "10.1016/j.ceramint.2014.04.023"
}

Kosanović, D., Zivojinović, J., Obradović, N., Pavlović, V. P., Pavlović, V., Peles, A.,& Ristić, M.M.. (2014). The influence of mechanical activation on the electrical properties of Ba0.77Sr0.23TiO3 ceramics. in Ceramics International
Elsevier Sci Ltd, Oxford., 40(8), 11883-11888.
https://doi.org/10.1016/j.ceramint.2014.04.023

Kosanović D, Zivojinović J, Obradović N, Pavlović VP, Pavlović V, Peles A, Ristić M. The influence of mechanical activation on the electrical properties of Ba0.77Sr0.23TiO3 ceramics. in Ceramics International. 2014;40(8):11883-11888.
doi:10.1016/j.ceramint.2014.04.023 .

Kosanović, Darko, Zivojinović, J., Obradović, N., Pavlović, Vera P., Pavlović, Vladimir, Peles, A., Ristić, M.M., "The influence of mechanical activation on the electrical properties of Ba0.77Sr0.23TiO3 ceramics" in Ceramics International, 40, no. 8 (2014):11883-11888,
https://doi.org/10.1016/j.ceramint.2014.04.023 . .

TY  - JOUR
AU  - Peles, A.
AU  - Djordjević, N.
AU  - Obradović, N.
AU  - Tadić, N.
AU  - Pavlović, Vladimir
PY  - 2013
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3320
AB  - Mechanical activation is a commonly used and relatively fast and inexpensive procedure for sample preparation before the sintering process. Cordierite, a stoichiometric mixture of three different oxides (2MgO center dot 2Al(2)O(3)center dot 5SiO(2)) is a very attractive, widely used high-temperature ceramic material. The mechanical activation of the starting mixtures with 5.00 mass% TiO2 was performed in a high energy ball mill during 10-80 min. The applied compaction pressure before the sintering process was 2t/cm(2), based on our recent investigation. The sintering process was performed at 1350 degrees C for 2h and 4h in air atmosphere. X-ray diffraction was used to analyze the phase composition of non-activated and 80 min activated samples, sintered for 2 and 4h, respectively. Scanning electron microscopy was performed to analyze the microstructure of both compacted and sintered samples. Atomic force microscope was used to investigate the surface of the sintered samples. This paper investigates the influence of prolonged sintering time on the densities of the sintered samples, along with electrical properties.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Influence of Prolonged Sintering Time on Density and Electrical Properties of Isothermally Sintered Cordierite-based Ceramics
EP  - 164
IS  - 2
SP  - 157
VL  - 45
DO  - 10.2298/SOS1302157P
ER  - 

@article{
author = "Peles, A. and Djordjević, N. and Obradović, N. and Tadić, N. and Pavlović, Vladimir",
year = "2013",
abstract = "Mechanical activation is a commonly used and relatively fast and inexpensive procedure for sample preparation before the sintering process. Cordierite, a stoichiometric mixture of three different oxides (2MgO center dot 2Al(2)O(3)center dot 5SiO(2)) is a very attractive, widely used high-temperature ceramic material. The mechanical activation of the starting mixtures with 5.00 mass% TiO2 was performed in a high energy ball mill during 10-80 min. The applied compaction pressure before the sintering process was 2t/cm(2), based on our recent investigation. The sintering process was performed at 1350 degrees C for 2h and 4h in air atmosphere. X-ray diffraction was used to analyze the phase composition of non-activated and 80 min activated samples, sintered for 2 and 4h, respectively. Scanning electron microscopy was performed to analyze the microstructure of both compacted and sintered samples. Atomic force microscope was used to investigate the surface of the sintered samples. This paper investigates the influence of prolonged sintering time on the densities of the sintered samples, along with electrical properties.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Influence of Prolonged Sintering Time on Density and Electrical Properties of Isothermally Sintered Cordierite-based Ceramics",
pages = "164-157",
number = "2",
volume = "45",
doi = "10.2298/SOS1302157P"
}

Peles, A., Djordjević, N., Obradović, N., Tadić, N.,& Pavlović, V.. (2013). Influence of Prolonged Sintering Time on Density and Electrical Properties of Isothermally Sintered Cordierite-based Ceramics. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 45(2), 157-164.
https://doi.org/10.2298/SOS1302157P

Peles A, Djordjević N, Obradović N, Tadić N, Pavlović V. Influence of Prolonged Sintering Time on Density and Electrical Properties of Isothermally Sintered Cordierite-based Ceramics. in Science of Sintering. 2013;45(2):157-164.
doi:10.2298/SOS1302157P .

Peles, A., Djordjević, N., Obradović, N., Tadić, N., Pavlović, Vladimir, "Influence of Prolonged Sintering Time on Density and Electrical Properties of Isothermally Sintered Cordierite-based Ceramics" in Science of Sintering, 45, no. 2 (2013):157-164,
https://doi.org/10.2298/SOS1302157P . .