Rogan, Jelena

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5785ea73-569d-416f-a521-aea690898106
  • Rogan, Jelena (10)
  • Rogan, Jelena R. (1)

Author's Bibliography

Morphological and structural characterization of MgAl2O4 spinel.

Obradović, Nina; Filipović, Suzana; Fahrenholtz, William G.; Marinkovic, Bojan A.; Rogan, Jelena; Lević, Steva; Đorđević, Antonije; Pavlović, Vladimir B.

TY  - JOUR
AU  - Obradović, Nina
AU  - Filipović, Suzana
AU  - Fahrenholtz, William G.
AU  - Marinkovic, Bojan A.
AU  - Rogan, Jelena
AU  - Lević, Steva
AU  - Đorđević, Antonije
AU  - Pavlović, Vladimir B.
UR  - https://doiserbia.nb.rs/Article.aspx?ID=0350-820X2301001O
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/6372
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 1800o 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.
T2  - Science of Sintering, 55 (2023) 1-10
T1  - Morphological and structural characterization of MgAl2O4 spinel.
DO  - 10.2298/SOS2301001O
ER  - 
@article{
author = "Obradović, Nina and Filipović, Suzana and Fahrenholtz, William G. and Marinkovic, Bojan A. and Rogan, Jelena and Lević, Steva and Đorđević, Antonije and Pavlović, Vladimir B.",
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 1800o 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.",
journal = "Science of Sintering, 55 (2023) 1-10",
title = "Morphological and structural characterization of MgAl2O4 spinel.",
doi = "10.2298/SOS2301001O"
}
Obradović, N., Filipović, S., Fahrenholtz, W. G., Marinkovic, B. A., Rogan, J., Lević, S., Đorđević, A.,& Pavlović, V. B..Morphological and structural characterization of MgAl2O4 spinel.. in Science of Sintering, 55 (2023) 1-10.
https://doi.org/10.2298/SOS2301001O
Obradović N, Filipović S, Fahrenholtz WG, Marinkovic BA, Rogan J, Lević S, Đorđević A, Pavlović VB. Morphological and structural characterization of MgAl2O4 spinel.. in Science of Sintering, 55 (2023) 1-10..
doi:10.2298/SOS2301001O .
Obradović, Nina, Filipović, Suzana, Fahrenholtz, William G., Marinkovic, Bojan A., Rogan, Jelena, Lević, Steva, Đorđević, Antonije, Pavlović, Vladimir B., "Morphological and structural characterization of MgAl2O4 spinel." in Science of Sintering, 55 (2023) 1-10,
https://doi.org/10.2298/SOS2301001O . .

Effect of Mechanical Activation on the Densification Behavior of MgAl2O4 Spinel

Obradović, Nina; Fahrenholtz, William G.; Filipović, Suzana; Đorđević, Pavle; Rogan, Jelena; Pavlović, Vladimir

(The Ceramic Society of Japan, 2019)

TY  - CONF
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Filipović, Suzana
AU  - Đorđević, Pavle
AU  - Rogan, Jelena
AU  - Pavlović, Vladimir
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/7050
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5757
AB  - Magnesium aluminate and other alumina-based spinels attract attention due to their high hardness, high mechanical strength, and low dielectric constant. MgAl2O4 was produced by solid-state reaction between MgO and a-Al2O3 powders. Mechanical activation was used to increase the reactivity of powders and decrease the sintering temperatures. Mechanical activation of mixed powders was performed in a high-energy planetary ball mill in air for 30, 60, 90, and 120 minutes. The resulting powders were characterized to determine the effect of activation on surface area, particle size, and crystallinity. Mechanical activation decreased particle size, increased surface area, and increased the width of peaks in x-ray diffraction. Dilatometry was used to monitor densification behavior up to 1500 °C. For non-activated powders, sintering started at approximately 1400 °C, while for activated powders, the onset temperature decreased to about 1340 °C. Mechanical activation is an efficient method to improve the densification behaviour of MgAl2O4 produced from mixed oxide powders.
PB  - The Ceramic Society of Japan
C3  - The 13th Pacific Rim Conference of Ceramic Societies (PACRIM13), October 27 - November 1, 2019, Okinawa Convention Center, Japan
T1  - Effect of Mechanical Activation on the Densification Behavior of MgAl2O4 Spinel
SP  - 30-B1C-S13-14
UR  - https://hdl.handle.net/21.15107/rcub_dais_7050
ER  - 
@conference{
author = "Obradović, Nina and Fahrenholtz, William G. and Filipović, Suzana and Đorđević, Pavle and Rogan, Jelena and Pavlović, Vladimir",
year = "2019",
abstract = "Magnesium aluminate and other alumina-based spinels attract attention due to their high hardness, high mechanical strength, and low dielectric constant. MgAl2O4 was produced by solid-state reaction between MgO and a-Al2O3 powders. Mechanical activation was used to increase the reactivity of powders and decrease the sintering temperatures. Mechanical activation of mixed powders was performed in a high-energy planetary ball mill in air for 30, 60, 90, and 120 minutes. The resulting powders were characterized to determine the effect of activation on surface area, particle size, and crystallinity. Mechanical activation decreased particle size, increased surface area, and increased the width of peaks in x-ray diffraction. Dilatometry was used to monitor densification behavior up to 1500 °C. For non-activated powders, sintering started at approximately 1400 °C, while for activated powders, the onset temperature decreased to about 1340 °C. Mechanical activation is an efficient method to improve the densification behaviour of MgAl2O4 produced from mixed oxide powders.",
publisher = "The Ceramic Society of Japan",
journal = "The 13th Pacific Rim Conference of Ceramic Societies (PACRIM13), October 27 - November 1, 2019, Okinawa Convention Center, Japan",
title = "Effect of Mechanical Activation on the Densification Behavior of MgAl2O4 Spinel",
pages = "30-B1C-S13-14",
url = "https://hdl.handle.net/21.15107/rcub_dais_7050"
}
Obradović, N., Fahrenholtz, W. G., Filipović, S., Đorđević, P., Rogan, J.,& Pavlović, V.. (2019). Effect of Mechanical Activation on the Densification Behavior of MgAl2O4 Spinel. in The 13th Pacific Rim Conference of Ceramic Societies (PACRIM13), October 27 - November 1, 2019, Okinawa Convention Center, Japan
The Ceramic Society of Japan., 30-B1C-S13-14.
https://hdl.handle.net/21.15107/rcub_dais_7050
Obradović N, Fahrenholtz WG, Filipović S, Đorđević P, Rogan J, Pavlović V. Effect of Mechanical Activation on the Densification Behavior of MgAl2O4 Spinel. in The 13th Pacific Rim Conference of Ceramic Societies (PACRIM13), October 27 - November 1, 2019, Okinawa Convention Center, Japan. 2019;:30-B1C-S13-14.
https://hdl.handle.net/21.15107/rcub_dais_7050 .
Obradović, Nina, Fahrenholtz, William G., Filipović, Suzana, Đorđević, Pavle, Rogan, Jelena, Pavlović, Vladimir, "Effect of Mechanical Activation on the Densification Behavior of MgAl2O4 Spinel" in The 13th Pacific Rim Conference of Ceramic Societies (PACRIM13), October 27 - November 1, 2019, Okinawa Convention Center, Japan (2019):30-B1C-S13-14,
https://hdl.handle.net/21.15107/rcub_dais_7050 .

The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics

Obradović, Nina; Fahrenholtz, William G.; Filipović, Suzana; Kosanović, Darko; Dapčević, Aleksandra; Rogan, Jelena; Pavlović, Vladimir

(Societa ceramica italiana, 2019)

TY  - CONF
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Filipović, Suzana
AU  - Kosanović, Darko
AU  - Dapčević, Aleksandra
AU  - Rogan, Jelena
AU  - Pavlović, Vladimir
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/7022
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5753
AB  - Magnesium aluminate, MgAl2O4, and other alumina-based spinels are refractory ceramics with high hardness and resistance to chemical attack while also being possible microwave dielectrics. Pure MgAl2O4 can be optically transparent when fully dense. Spinels exhibit inversion, which results in disorder among occupancy of A and B site cations. The goal of this study was to examine the effects of mechanical activation and composition on the temperature required for spinel formation and the site occupancy in the resulting spinel. 
MgAl2O4 was produced by solid state reaction between MgO and alpha-Al2O3. The starting powders were mixed by ball milling to homogenize the powders 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 1500 °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 influence of milling and consolidation parameters were studied by electrical measurements and mechanical characterization. 
The main results of this study were that mechanical activation for 60 minutes initiated a mechano-chemical reaction, and resulted in spinel formation at much lower temperatures than within non-activated powders. Microstructures of ceramics sintered below 1400 oC indicated that final stage sintering started at much lower temperatures for activated samples than for non-activated samples. 
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  - Societa ceramica italiana
PB  - Politecnico di Torino
C3  - Abstract Book / XVI Conference and Exhibition of the European Ceramic Society XVI ECerS Conference, Torino, 16-20 June 2019
T1  - The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics
EP  - 262
SP  - 262
UR  - https://hdl.handle.net/21.15107/rcub_dais_7022
ER  - 
@conference{
author = "Obradović, Nina and Fahrenholtz, William G. and Filipović, Suzana and Kosanović, Darko and Dapčević, Aleksandra and Rogan, Jelena and Pavlović, Vladimir",
year = "2019",
abstract = "Magnesium aluminate, MgAl2O4, and other alumina-based spinels are refractory ceramics with high hardness and resistance to chemical attack while also being possible microwave dielectrics. Pure MgAl2O4 can be optically transparent when fully dense. Spinels exhibit inversion, which results in disorder among occupancy of A and B site cations. The goal of this study was to examine the effects of mechanical activation and composition on the temperature required for spinel formation and the site occupancy in the resulting spinel. 
MgAl2O4 was produced by solid state reaction between MgO and alpha-Al2O3. The starting powders were mixed by ball milling to homogenize the powders 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 1500 °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 influence of milling and consolidation parameters were studied by electrical measurements and mechanical characterization. 
The main results of this study were that mechanical activation for 60 minutes initiated a mechano-chemical reaction, and resulted in spinel formation at much lower temperatures than within non-activated powders. Microstructures of ceramics sintered below 1400 oC indicated that final stage sintering started at much lower temperatures for activated samples than for non-activated samples. 
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 = "Societa ceramica italiana, Politecnico di Torino",
journal = "Abstract Book / XVI Conference and Exhibition of the European Ceramic Society XVI ECerS Conference, Torino, 16-20 June 2019",
title = "The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics",
pages = "262-262",
url = "https://hdl.handle.net/21.15107/rcub_dais_7022"
}
Obradović, N., Fahrenholtz, W. G., Filipović, S., Kosanović, D., Dapčević, A., Rogan, J.,& Pavlović, V.. (2019). The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics. in Abstract Book / XVI Conference and Exhibition of the European Ceramic Society XVI ECerS Conference, Torino, 16-20 June 2019
Societa ceramica italiana., 262-262.
https://hdl.handle.net/21.15107/rcub_dais_7022
Obradović N, Fahrenholtz WG, Filipović S, Kosanović D, Dapčević A, Rogan J, Pavlović V. The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics. in Abstract Book / XVI Conference and Exhibition of the European Ceramic Society XVI ECerS Conference, Torino, 16-20 June 2019. 2019;:262-262.
https://hdl.handle.net/21.15107/rcub_dais_7022 .
Obradović, Nina, Fahrenholtz, William G., Filipović, Suzana, Kosanović, Darko, Dapčević, Aleksandra, Rogan, Jelena, Pavlović, Vladimir, "The effect of mechanical activation on synthesis and properties of MgAl2O4 ceramics" in Abstract Book / XVI Conference and Exhibition of the European Ceramic Society XVI ECerS Conference, Torino, 16-20 June 2019 (2019):262-262,
https://hdl.handle.net/21.15107/rcub_dais_7022 .

Morphological and structural characterization of spinel MgAl2O4

Filipović, Suzana; Obradović, Nina; Fahrenholtz, William G.; Marinković, Bojan A.; Rogan, Jelena; Lević, S.; Pavlović, Vladimir

(Belgrade : Serbian Ceramic Society, 2019)

TY  - CONF
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Marinković, Bojan A.
AU  - Rogan, Jelena
AU  - Lević, S.
AU  - Pavlović, Vladimir
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/6779
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5743
AB  - Magnesium aluminate has spinel structure and very good mechanical, chemical, and thermal properties. Owing to these properties, it 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 using for integrated electronic devices, as well. Furthermore, as a porous ceramic, magnesium aluminate has important application as humidity sensor, catalyst and filter for waste water purification. In this paper, synthesis and characterization of MgAl2O4 was performed. Stochiometric ratio of MgO and Al2O3powders was mixed and calcined within the temperatures range 1500-1800 oC to produce pure spinel phase. Thereafter pellets were crushed and treated in planetary ball mill for 60 minutes to obtained fine grain. All powders, calcined and milled, were examined for phase composition, crystal structure, and morphology. The obtained results showed that by increasing the temperature denser samples but more fragile have been synthesized. Milling for 1 hour leads to crumble of bigger particles and getting finer, single phase powders. XRPD and Raman spectroscopy showed disorder in crystal structure after milling.
PB  - Belgrade : Serbian Ceramic Society
C3  - Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019
T1  - Morphological and structural characterization of spinel MgAl2O4
EP  - 32
SP  - 32
UR  - https://hdl.handle.net/21.15107/rcub_dais_6779
ER  - 
@conference{
author = "Filipović, Suzana and Obradović, Nina and Fahrenholtz, William G. and Marinković, Bojan A. and Rogan, Jelena and Lević, S. and Pavlović, Vladimir",
year = "2019",
abstract = "Magnesium aluminate has spinel structure and very good mechanical, chemical, and thermal properties. Owing to these properties, it 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 using for integrated electronic devices, as well. Furthermore, as a porous ceramic, magnesium aluminate has important application as humidity sensor, catalyst and filter for waste water purification. In this paper, synthesis and characterization of MgAl2O4 was performed. Stochiometric ratio of MgO and Al2O3powders was mixed and calcined within the temperatures range 1500-1800 oC to produce pure spinel phase. Thereafter pellets were crushed and treated in planetary ball mill for 60 minutes to obtained fine grain. All powders, calcined and milled, were examined for phase composition, crystal structure, and morphology. The obtained results showed that by increasing the temperature denser samples but more fragile have been synthesized. Milling for 1 hour leads to crumble of bigger particles and getting finer, single phase powders. XRPD and Raman spectroscopy showed disorder in crystal structure after milling.",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019",
title = "Morphological and structural characterization of spinel MgAl2O4",
pages = "32-32",
url = "https://hdl.handle.net/21.15107/rcub_dais_6779"
}
Filipović, S., Obradović, N., Fahrenholtz, W. G., Marinković, B. A., Rogan, J., Lević, S.,& Pavlović, V.. (2019). Morphological and structural characterization of spinel MgAl2O4. in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019
Belgrade : Serbian Ceramic Society., 32-32.
https://hdl.handle.net/21.15107/rcub_dais_6779
Filipović S, Obradović N, Fahrenholtz WG, Marinković BA, Rogan J, Lević S, Pavlović V. Morphological and structural characterization of spinel MgAl2O4. in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019. 2019;:32-32.
https://hdl.handle.net/21.15107/rcub_dais_6779 .
Filipović, Suzana, Obradović, Nina, Fahrenholtz, William G., Marinković, Bojan A., Rogan, Jelena, Lević, S., Pavlović, Vladimir, "Morphological and structural characterization of spinel MgAl2O4" in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019 (2019):32-32,
https://hdl.handle.net/21.15107/rcub_dais_6779 .

Characterization of MgAl2O4 sintered ceramics

Obradović, Nina; Fahrenholtz, William G.; Filipović, Suzana; Đorđević, Pavle; Marković, Smilja; Rogan, Jelena; Vulić, Predrag J.; Pavlović, Vladimir

(Belgrade : Serbian Ceramic Society, 2019)

TY  - CONF
AU  - Obradović, Nina
AU  - Fahrenholtz, William G.
AU  - Filipović, Suzana
AU  - Đorđević, Pavle
AU  - Marković, Smilja
AU  - Rogan, Jelena
AU  - Vulić, Predrag J.
AU  - Pavlović, Vladimir
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/6980
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5748
AB  - Single crystalline phase MgAl2O4 is made from the predetermined composition of MgO-Al2O3 powder mixture by using ball-milling. Mixtures of MgO and Al2O3 are treated in planetary ball mill for 30, 60, 90 and 120 minutes, in air. The aim of this experiment was to examine phase composition, microstructure, and densification behavior of all sintered samples and to find out which sample has the best features for further use. After sintering in dilatometer at 1500 °C, XRD patterns and SEM images were recorded. The results show that mechanical activation is an efficient method to improve the densification behavior of MgAl2O4 sintered specimens. With the prolonged milling time, densities increased, reaching the maximum value of 2.8 g/cm3 for sample activated 120 minutes.
PB  - Belgrade : Serbian Ceramic Society
C3  - Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019
T1  - Characterization of MgAl2O4 sintered ceramics
EP  - 54
SP  - 54
UR  - https://hdl.handle.net/21.15107/rcub_dais_6980
ER  - 
@conference{
author = "Obradović, Nina and Fahrenholtz, William G. and Filipović, Suzana and Đorđević, Pavle and Marković, Smilja and Rogan, Jelena and Vulić, Predrag J. and Pavlović, Vladimir",
year = "2019",
abstract = "Single crystalline phase MgAl2O4 is made from the predetermined composition of MgO-Al2O3 powder mixture by using ball-milling. Mixtures of MgO and Al2O3 are treated in planetary ball mill for 30, 60, 90 and 120 minutes, in air. The aim of this experiment was to examine phase composition, microstructure, and densification behavior of all sintered samples and to find out which sample has the best features for further use. After sintering in dilatometer at 1500 °C, XRD patterns and SEM images were recorded. The results show that mechanical activation is an efficient method to improve the densification behavior of MgAl2O4 sintered specimens. With the prolonged milling time, densities increased, reaching the maximum value of 2.8 g/cm3 for sample activated 120 minutes.",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019",
title = "Characterization of MgAl2O4 sintered ceramics",
pages = "54-54",
url = "https://hdl.handle.net/21.15107/rcub_dais_6980"
}
Obradović, N., Fahrenholtz, W. G., Filipović, S., Đorđević, P., Marković, S., Rogan, J., Vulić, P. J.,& Pavlović, V.. (2019). Characterization of MgAl2O4 sintered ceramics. in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019
Belgrade : Serbian Ceramic Society., 54-54.
https://hdl.handle.net/21.15107/rcub_dais_6980
Obradović N, Fahrenholtz WG, Filipović S, Đorđević P, Marković S, Rogan J, Vulić PJ, Pavlović V. Characterization of MgAl2O4 sintered ceramics. in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019. 2019;:54-54.
https://hdl.handle.net/21.15107/rcub_dais_6980 .
Obradović, Nina, Fahrenholtz, William G., Filipović, Suzana, Đorđević, Pavle, Marković, Smilja, Rogan, Jelena, Vulić, Predrag J., Pavlović, Vladimir, "Characterization of MgAl2O4 sintered ceramics" in Program and the Book of abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VIII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 23-25. September 2019 (2019):54-54,
https://hdl.handle.net/21.15107/rcub_dais_6980 .

Sintering of alumina doped with different oxides, followed by sensitive dilatometer

Filipović, Suzana; Obradović, Nina; Marković, Smilja; Đorđević, Antonije; Dapčević, Aleksandra; Rogan, Jelena; Pavlović, Vladimir B.

(Belgrade : Materials Research Society of Serbia, 2018)

TY  - CONF
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Marković, Smilja
AU  - Đorđević, Antonije
AU  - Dapčević, Aleksandra
AU  - Rogan, Jelena
AU  - Pavlović, Vladimir B.
PY  - 2018
UR  - http://dais.sanu.ac.rs/123456789/3634
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5725
AB  - Sintered alumina powder represents suitable material for usage in various industry fields (e.g., as chip carriers in electronics, microwaves, jewelry production), due to convenient physical properties, such as sinterability, electrical and mechanical features. Those properties can be modified by addition of different oxides and/or mechanical treatment. Therefore, in this investigation the alumina was doped with 1 wt. % of Cr2O3, Mn2O3 and NiO, respectively, followed by 1 hour of mechanical activation at 400 rpm in planetary ball mill. Sintering of powder mixtures was tracked by sensitive dilatometer up to 1400 °C. The final density values varied from cca. 2 ̶ 3.2 g/cm3. Changes in microstructure were observed by means of SEM. The influence of additives along with mechanical activation is monitored trough changes in electrical permittivity and loss tangent. Compared to pure alumina, the additives lower the relative permittivity and increase dielectric losses. For a given mixture, the sintering increases the relative permittivity and decreases losses.
PB  - Belgrade : Materials Research Society of Serbia
C3  - Programme and The Book of Abstracts / Twentieth Annual Conference YUCOMAT 2018, Herceg Novi, September 3-7, 2018
T1  - Sintering of alumina doped with different oxides, followed by sensitive dilatometer
EP  - 95
SP  - 95
UR  - https://hdl.handle.net/21.15107/rcub_dais_3634
ER  - 
@conference{
author = "Filipović, Suzana and Obradović, Nina and Marković, Smilja and Đorđević, Antonije and Dapčević, Aleksandra and Rogan, Jelena and Pavlović, Vladimir B.",
year = "2018",
abstract = "Sintered alumina powder represents suitable material for usage in various industry fields (e.g., as chip carriers in electronics, microwaves, jewelry production), due to convenient physical properties, such as sinterability, electrical and mechanical features. Those properties can be modified by addition of different oxides and/or mechanical treatment. Therefore, in this investigation the alumina was doped with 1 wt. % of Cr2O3, Mn2O3 and NiO, respectively, followed by 1 hour of mechanical activation at 400 rpm in planetary ball mill. Sintering of powder mixtures was tracked by sensitive dilatometer up to 1400 °C. The final density values varied from cca. 2 ̶ 3.2 g/cm3. Changes in microstructure were observed by means of SEM. The influence of additives along with mechanical activation is monitored trough changes in electrical permittivity and loss tangent. Compared to pure alumina, the additives lower the relative permittivity and increase dielectric losses. For a given mixture, the sintering increases the relative permittivity and decreases losses.",
publisher = "Belgrade : Materials Research Society of Serbia",
journal = "Programme and The Book of Abstracts / Twentieth Annual Conference YUCOMAT 2018, Herceg Novi, September 3-7, 2018",
title = "Sintering of alumina doped with different oxides, followed by sensitive dilatometer",
pages = "95-95",
url = "https://hdl.handle.net/21.15107/rcub_dais_3634"
}
Filipović, S., Obradović, N., Marković, S., Đorđević, A., Dapčević, A., Rogan, J.,& Pavlović, V. B.. (2018). Sintering of alumina doped with different oxides, followed by sensitive dilatometer. in Programme and The Book of Abstracts / Twentieth Annual Conference YUCOMAT 2018, Herceg Novi, September 3-7, 2018
Belgrade : Materials Research Society of Serbia., 95-95.
https://hdl.handle.net/21.15107/rcub_dais_3634
Filipović S, Obradović N, Marković S, Đorđević A, Dapčević A, Rogan J, Pavlović VB. Sintering of alumina doped with different oxides, followed by sensitive dilatometer. in Programme and The Book of Abstracts / Twentieth Annual Conference YUCOMAT 2018, Herceg Novi, September 3-7, 2018. 2018;:95-95.
https://hdl.handle.net/21.15107/rcub_dais_3634 .
Filipović, Suzana, Obradović, Nina, Marković, Smilja, Đorđević, Antonije, Dapčević, Aleksandra, Rogan, Jelena, Pavlović, Vladimir B., "Sintering of alumina doped with different oxides, followed by sensitive dilatometer" in Programme and The Book of Abstracts / Twentieth Annual Conference YUCOMAT 2018, Herceg Novi, September 3-7, 2018 (2018):95-95,
https://hdl.handle.net/21.15107/rcub_dais_3634 .

Effects of ball-milling on properties of sintered alumina doped with Mn2O3

Filipović, Suzana; Obradović, Nina; Marković, Smilja; Mitrić, Miodrag; Đorđević, Antonije; Dapčević, Aleksandra; Rogan, Jelena; Pavlović, Vladimir B.

(Belgrade : Serbian Ceramic Society, 2018)

TY  - CONF
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Marković, Smilja
AU  - Mitrić, Miodrag
AU  - Đorđević, Antonije
AU  - Dapčević, Aleksandra
AU  - Rogan, Jelena
AU  - Pavlović, Vladimir B.
PY  - 2018
UR  - http://dais.sanu.ac.rs/123456789/4114
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/5731
AB  - Recently, with the huge use of smart gadgets, developing of smart jewelry represents a very interesting segment in material science, as well as in electronic science. Alumina is widely used ceramic in many industrial fields as pigments, catalysis, microelectronics, etc., mostly because of its low cost and appropriate mechanical and electrical properties, high surface area and thermal stability. Also, modified alumina could be applied in production of smart jewelry. Thus, the main objectives of this investigation is to improve features of sintered alumina doped with Mn2O3 along with mechanical treatment, in order to obtain strong ceramic with low values of dielectric loss and low relative dielectric permittivity, as well as esthetic. Commercial alumina powder was doped with 1 wt % of manganese oxide and treated in planetary ball mill for an hour. Characteristic temperatures of both powders (non-activated and activated one) were investigated in detail by DTA and TG analyses. After sintering at 1200, 1300, and 1400 oC for 2 h, XRD patterns and SEM images were recorded. Furthermore, mechanical and electrical properties were examined for all sintered samples.
PB  - Belgrade : Serbian Ceramic Society
C3  - Program and the Book of Abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 17-19 September 2018
T1  - Effects of ball-milling on properties of sintered alumina doped with Mn2O3
EP  - 75
SP  - 75
UR  - https://hdl.handle.net/21.15107/rcub_dais_4114
ER  - 
@conference{
author = "Filipović, Suzana and Obradović, Nina and Marković, Smilja and Mitrić, Miodrag and Đorđević, Antonije and Dapčević, Aleksandra and Rogan, Jelena and Pavlović, Vladimir B.",
year = "2018",
abstract = "Recently, with the huge use of smart gadgets, developing of smart jewelry represents a very interesting segment in material science, as well as in electronic science. Alumina is widely used ceramic in many industrial fields as pigments, catalysis, microelectronics, etc., mostly because of its low cost and appropriate mechanical and electrical properties, high surface area and thermal stability. Also, modified alumina could be applied in production of smart jewelry. Thus, the main objectives of this investigation is to improve features of sintered alumina doped with Mn2O3 along with mechanical treatment, in order to obtain strong ceramic with low values of dielectric loss and low relative dielectric permittivity, as well as esthetic. Commercial alumina powder was doped with 1 wt % of manganese oxide and treated in planetary ball mill for an hour. Characteristic temperatures of both powders (non-activated and activated one) were investigated in detail by DTA and TG analyses. After sintering at 1200, 1300, and 1400 oC for 2 h, XRD patterns and SEM images were recorded. Furthermore, mechanical and electrical properties were examined for all sintered samples.",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Program and the Book of Abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 17-19 September 2018",
title = "Effects of ball-milling on properties of sintered alumina doped with Mn2O3",
pages = "75-75",
url = "https://hdl.handle.net/21.15107/rcub_dais_4114"
}
Filipović, S., Obradović, N., Marković, S., Mitrić, M., Đorđević, A., Dapčević, A., Rogan, J.,& Pavlović, V. B.. (2018). Effects of ball-milling on properties of sintered alumina doped with Mn2O3. in Program and the Book of Abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 17-19 September 2018
Belgrade : Serbian Ceramic Society., 75-75.
https://hdl.handle.net/21.15107/rcub_dais_4114
Filipović S, Obradović N, Marković S, Mitrić M, Đorđević A, Dapčević A, Rogan J, Pavlović VB. Effects of ball-milling on properties of sintered alumina doped with Mn2O3. in Program and the Book of Abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 17-19 September 2018. 2018;:75-75.
https://hdl.handle.net/21.15107/rcub_dais_4114 .
Filipović, Suzana, Obradović, Nina, Marković, Smilja, Mitrić, Miodrag, Đorđević, Antonije, Dapčević, Aleksandra, Rogan, Jelena, Pavlović, Vladimir B., "Effects of ball-milling on properties of sintered alumina doped with Mn2O3" in Program and the Book of Abstracts / Serbian Ceramic Society Conference Advanced Ceramics and Application VII : New Frontiers in Multifunctional Material Science and Processing, Serbia, Belgrade, 17-19 September 2018 (2018):75-75,
https://hdl.handle.net/21.15107/rcub_dais_4114 .

Physical Properties of Sintered Alumina Doped with Different Oxides

Filipović, Suzana; Obradović, Nina; Marković, Smilja; Djordjević, Antonije; Balac, Igor; Dapcević, Aleksandra; Rogan, Jelena; Pavlović, Vladimir

(Međunarodni Institut za nauku o sinterovanju, Beograd, 2018)

TY  - JOUR
AU  - Filipović, Suzana
AU  - Obradović, Nina
AU  - Marković, Smilja
AU  - Djordjević, Antonije
AU  - Balac, Igor
AU  - Dapcević, Aleksandra
AU  - Rogan, Jelena
AU  - Pavlović, Vladimir
PY  - 2018
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/4712
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 Djordjević, Antonije and Balac, Igor and Dapcević, Aleksandra and Rogan, Jelena and Pavlović, Vladimir",
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., Djordjević, A., Balac, I., Dapcević, A., Rogan, J.,& Pavlović, V.. (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, Djordjević A, Balac I, Dapcević A, Rogan J, Pavlović V. 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, Djordjević, Antonije, Balac, Igor, Dapcević, Aleksandra, Rogan, Jelena, Pavlović, Vladimir, "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 . .
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Structural, thermal and surface characterization of thermoplastic polyurethanes based on poly(dimethylsiloxane)

Pergal, Marija V.; Stefanović, Ivan S.; Godjevac, Dejan; Antić, Vesna; Milacić, Vesna; Ostojić, Sanja; Rogan, Jelena; Djonlagić, Jasna

(Srpsko hemijsko društvo, Beograd, 2014)

TY  - JOUR
AU  - Pergal, Marija V.
AU  - Stefanović, Ivan S.
AU  - Godjevac, Dejan
AU  - Antić, Vesna
AU  - Milacić, Vesna
AU  - Ostojić, Sanja
AU  - Rogan, Jelena
AU  - Djonlagić, Jasna
PY  - 2014
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3399
AB  - In this study, the synthesis, structure and physical properties of two series of thermoplastic polyurethanes based on hydroxypropyl-terminated poly(dimethylsiloxane) (HP-PDMS) or hydroxyethoxypropyl-terminated poly(dimethylsiloxane) (EO-PDMS) as soft segments, and 4,4'-methylenediphenyl diisocyanate and 1,4-butanediol as hard segments were investigated. The polyurethanes were synthesized by two-step polyaddition in solution. The effects of the type and content of PDMS segments on the structure, thermal and surface properties of copolymers were studied by H-1-, C-13-nuclear magnetic resonance (NMR) spectroscopy and two-dimensional NMR spectroscopies (heteronuclear multiple bond correlation (HMBC) and rotating-frame nuclear Overhauser effect (ROESY)), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide-angle X-ray scattering (WAXS), scanning electron microscopy (SEM) and water contact angle and water absorption measurements. Thermal properties investigated by DSC indicated that the presence of soft PDMS segments lowers the glass transition and melting temperatures of the hard phase as well as the degree of crystallinity. SEM analysis of the copolymers with a lower soft segment content confirmed the presence of spherulite superstructures, which arise from the crystallization of the hard segments. When compared with polyurethanes prepared from HP-PDMS, the copolymers synthesized from EO-PDMS with the same content of the soft segments had a higher degree of crystallinity, better thermal stability and a less hydrophobic surface. The obtained results showed that the synthesized polyurethanes had good thermal and surface properties, which could be further modified by changing the type or content of the soft segments.
PB  - Srpsko hemijsko društvo, Beograd
T2  - JOURNAL OF THE SERBIAN CHEMICAL SOCIETY
T1  - Structural, thermal and surface characterization of thermoplastic polyurethanes based on poly(dimethylsiloxane)
EP  - +
IS  - 7
SP  - 843
VL  - 79
DO  - 10.2298/JSC130819149P
ER  - 
@article{
author = "Pergal, Marija V. and Stefanović, Ivan S. and Godjevac, Dejan and Antić, Vesna and Milacić, Vesna and Ostojić, Sanja and Rogan, Jelena and Djonlagić, Jasna",
year = "2014",
abstract = "In this study, the synthesis, structure and physical properties of two series of thermoplastic polyurethanes based on hydroxypropyl-terminated poly(dimethylsiloxane) (HP-PDMS) or hydroxyethoxypropyl-terminated poly(dimethylsiloxane) (EO-PDMS) as soft segments, and 4,4'-methylenediphenyl diisocyanate and 1,4-butanediol as hard segments were investigated. The polyurethanes were synthesized by two-step polyaddition in solution. The effects of the type and content of PDMS segments on the structure, thermal and surface properties of copolymers were studied by H-1-, C-13-nuclear magnetic resonance (NMR) spectroscopy and two-dimensional NMR spectroscopies (heteronuclear multiple bond correlation (HMBC) and rotating-frame nuclear Overhauser effect (ROESY)), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide-angle X-ray scattering (WAXS), scanning electron microscopy (SEM) and water contact angle and water absorption measurements. Thermal properties investigated by DSC indicated that the presence of soft PDMS segments lowers the glass transition and melting temperatures of the hard phase as well as the degree of crystallinity. SEM analysis of the copolymers with a lower soft segment content confirmed the presence of spherulite superstructures, which arise from the crystallization of the hard segments. When compared with polyurethanes prepared from HP-PDMS, the copolymers synthesized from EO-PDMS with the same content of the soft segments had a higher degree of crystallinity, better thermal stability and a less hydrophobic surface. The obtained results showed that the synthesized polyurethanes had good thermal and surface properties, which could be further modified by changing the type or content of the soft segments.",
publisher = "Srpsko hemijsko društvo, Beograd",
journal = "JOURNAL OF THE SERBIAN CHEMICAL SOCIETY",
title = "Structural, thermal and surface characterization of thermoplastic polyurethanes based on poly(dimethylsiloxane)",
pages = "+-843",
number = "7",
volume = "79",
doi = "10.2298/JSC130819149P"
}
Pergal, M. V., Stefanović, I. S., Godjevac, D., Antić, V., Milacić, V., Ostojić, S., Rogan, J.,& Djonlagić, J.. (2014). Structural, thermal and surface characterization of thermoplastic polyurethanes based on poly(dimethylsiloxane). in JOURNAL OF THE SERBIAN CHEMICAL SOCIETY
Srpsko hemijsko društvo, Beograd., 79(7), 843-+.
https://doi.org/10.2298/JSC130819149P
Pergal MV, Stefanović IS, Godjevac D, Antić V, Milacić V, Ostojić S, Rogan J, Djonlagić J. Structural, thermal and surface characterization of thermoplastic polyurethanes based on poly(dimethylsiloxane). in JOURNAL OF THE SERBIAN CHEMICAL SOCIETY. 2014;79(7):843-+.
doi:10.2298/JSC130819149P .
Pergal, Marija V., Stefanović, Ivan S., Godjevac, Dejan, Antić, Vesna, Milacić, Vesna, Ostojić, Sanja, Rogan, Jelena, Djonlagić, Jasna, "Structural, thermal and surface characterization of thermoplastic polyurethanes based on poly(dimethylsiloxane)" in JOURNAL OF THE SERBIAN CHEMICAL SOCIETY, 79, no. 7 (2014):843-+,
https://doi.org/10.2298/JSC130819149P . .
13
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Influence of the chemical structure of poly(urea-urethane-siloxane)s on their morphological, surface and thermal properties

Balaban, Milica; Antić, Vesna; Pergal, Marija V.; Godjevac, Dejan; Francolini, Iolanda; Martinelli, Andrea; Rogan, Jelena; Djonlagić, Jasna

(Springer, New York, 2013)

TY  - JOUR
AU  - Balaban, Milica
AU  - Antić, Vesna
AU  - Pergal, Marija V.
AU  - Godjevac, Dejan
AU  - Francolini, Iolanda
AU  - Martinelli, Andrea
AU  - Rogan, Jelena
AU  - Djonlagić, Jasna
PY  - 2013
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3294
AB  - Segmented poly(urethane-urea-siloxane)s (PUUS) were synthesized using 4,4'-methylenediphenyl diisocyanate (MDI) and ethylene diamine (ED) as the hard segment components and hydroxypropyl-terminated poly(dimethylsiloxane) (PDMS) as the soft segment component, where the hard segment content ranged from 38 to 65 wt%. Segmented PUUSs were prepared by a two-step polymerization procedure in tetrahydrofuran/N-methylpyrrolidone (THF/NMP) mixture with a large proportion of polar solvent. The structure, composition and hard segment length were determined by C-13 NMR and two-dimensional correlation spectroscopy. Thermal, mechanical, small-angle X-ray scattering and hydrogen bonding analyses indicated the formation of the microphase-separated copolymers with high tensile strength. Globular superstructures observed in the copolymer films by scanning electron microscopy (SEM) and atomic force microscopy (AFM) were probably arisen from the microstructural organization of the MDI-ED segments, depending on their content and length. The PUUS copolymers showed high water resistance and became more hydrophobic with increasing weight fraction of PDMS.
PB  - Springer, New York
T2  - Polymer Bulletin
T1  - Influence of the chemical structure of poly(urea-urethane-siloxane)s on their morphological, surface and thermal properties
EP  - 2518
IS  - 9
SP  - 2493
VL  - 70
DO  - 10.1007/s00289-013-0968-2
ER  - 
@article{
author = "Balaban, Milica and Antić, Vesna and Pergal, Marija V. and Godjevac, Dejan and Francolini, Iolanda and Martinelli, Andrea and Rogan, Jelena and Djonlagić, Jasna",
year = "2013",
abstract = "Segmented poly(urethane-urea-siloxane)s (PUUS) were synthesized using 4,4'-methylenediphenyl diisocyanate (MDI) and ethylene diamine (ED) as the hard segment components and hydroxypropyl-terminated poly(dimethylsiloxane) (PDMS) as the soft segment component, where the hard segment content ranged from 38 to 65 wt%. Segmented PUUSs were prepared by a two-step polymerization procedure in tetrahydrofuran/N-methylpyrrolidone (THF/NMP) mixture with a large proportion of polar solvent. The structure, composition and hard segment length were determined by C-13 NMR and two-dimensional correlation spectroscopy. Thermal, mechanical, small-angle X-ray scattering and hydrogen bonding analyses indicated the formation of the microphase-separated copolymers with high tensile strength. Globular superstructures observed in the copolymer films by scanning electron microscopy (SEM) and atomic force microscopy (AFM) were probably arisen from the microstructural organization of the MDI-ED segments, depending on their content and length. The PUUS copolymers showed high water resistance and became more hydrophobic with increasing weight fraction of PDMS.",
publisher = "Springer, New York",
journal = "Polymer Bulletin",
title = "Influence of the chemical structure of poly(urea-urethane-siloxane)s on their morphological, surface and thermal properties",
pages = "2518-2493",
number = "9",
volume = "70",
doi = "10.1007/s00289-013-0968-2"
}
Balaban, M., Antić, V., Pergal, M. V., Godjevac, D., Francolini, I., Martinelli, A., Rogan, J.,& Djonlagić, J.. (2013). Influence of the chemical structure of poly(urea-urethane-siloxane)s on their morphological, surface and thermal properties. in Polymer Bulletin
Springer, New York., 70(9), 2493-2518.
https://doi.org/10.1007/s00289-013-0968-2
Balaban M, Antić V, Pergal MV, Godjevac D, Francolini I, Martinelli A, Rogan J, Djonlagić J. Influence of the chemical structure of poly(urea-urethane-siloxane)s on their morphological, surface and thermal properties. in Polymer Bulletin. 2013;70(9):2493-2518.
doi:10.1007/s00289-013-0968-2 .
Balaban, Milica, Antić, Vesna, Pergal, Marija V., Godjevac, Dejan, Francolini, Iolanda, Martinelli, Andrea, Rogan, Jelena, Djonlagić, Jasna, "Influence of the chemical structure of poly(urea-urethane-siloxane)s on their morphological, surface and thermal properties" in Polymer Bulletin, 70, no. 9 (2013):2493-2518,
https://doi.org/10.1007/s00289-013-0968-2 . .
12
8
15

Comparison of structural, textural and thermal characteristics of pure and acid treated bentonites from Aleksinac and Petrovac (Serbia)

Tomić, Zorica; Logar, Vesna P.; Babić, Biljana M.; Rogan, Jelena R.; Makreski, Petre

(Pergamon-Elsevier Science Ltd, Oxford, 2011)

TY  - JOUR
AU  - Tomić, Zorica
AU  - Logar, Vesna P.
AU  - Babić, Biljana M.
AU  - Rogan, Jelena R.
AU  - Makreski, Petre
PY  - 2011
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/2679
AB  - Bentonite samples collected from vicinity of Petrovac and Aleksinac were treated with different sulfuric acid molarities. Acid attack dissolved the octahedral sheets by interlayer and edge attack. The effects of the H2SO4 acid caused an exchange of Al3+, Fe3+ and Mg2+ with H. ions leading to a modification of the smectite crystalline structure. The Mg and Fe substitution in the octahedral sheets promoted the dispersion of corresponding layers and formation of amorphous silicon. The activated bentonites, after the treatment of sulfuric acid, exhibited a lower cation-exchange capacity (CEC)and significant increase of specific surface area from 6 to 387 m(2) g(-1) (bentonite from Petrovac) and from 11 to 306 m(2) g(-1) (bentonite from Aleksinac). The acid reaction caused a splitting of particles within the octahedral sheet which led to an increase in specific surface area and decrease in CEC in both bentonites.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Spectrochimica Acta Part A-Molecular and Biomolecular Spectroscopy
T1  - Comparison of structural, textural and thermal characteristics of pure and acid treated bentonites from Aleksinac and Petrovac (Serbia)
EP  - 395
IS  - 1
SP  - 389
VL  - 82
DO  - 10.1016/j.saa.2011.07.068
ER  - 
@article{
author = "Tomić, Zorica and Logar, Vesna P. and Babić, Biljana M. and Rogan, Jelena R. and Makreski, Petre",
year = "2011",
abstract = "Bentonite samples collected from vicinity of Petrovac and Aleksinac were treated with different sulfuric acid molarities. Acid attack dissolved the octahedral sheets by interlayer and edge attack. The effects of the H2SO4 acid caused an exchange of Al3+, Fe3+ and Mg2+ with H. ions leading to a modification of the smectite crystalline structure. The Mg and Fe substitution in the octahedral sheets promoted the dispersion of corresponding layers and formation of amorphous silicon. The activated bentonites, after the treatment of sulfuric acid, exhibited a lower cation-exchange capacity (CEC)and significant increase of specific surface area from 6 to 387 m(2) g(-1) (bentonite from Petrovac) and from 11 to 306 m(2) g(-1) (bentonite from Aleksinac). The acid reaction caused a splitting of particles within the octahedral sheet which led to an increase in specific surface area and decrease in CEC in both bentonites.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Spectrochimica Acta Part A-Molecular and Biomolecular Spectroscopy",
title = "Comparison of structural, textural and thermal characteristics of pure and acid treated bentonites from Aleksinac and Petrovac (Serbia)",
pages = "395-389",
number = "1",
volume = "82",
doi = "10.1016/j.saa.2011.07.068"
}
Tomić, Z., Logar, V. P., Babić, B. M., Rogan, J. R.,& Makreski, P.. (2011). Comparison of structural, textural and thermal characteristics of pure and acid treated bentonites from Aleksinac and Petrovac (Serbia). in Spectrochimica Acta Part A-Molecular and Biomolecular Spectroscopy
Pergamon-Elsevier Science Ltd, Oxford., 82(1), 389-395.
https://doi.org/10.1016/j.saa.2011.07.068
Tomić Z, Logar VP, Babić BM, Rogan JR, Makreski P. Comparison of structural, textural and thermal characteristics of pure and acid treated bentonites from Aleksinac and Petrovac (Serbia). in Spectrochimica Acta Part A-Molecular and Biomolecular Spectroscopy. 2011;82(1):389-395.
doi:10.1016/j.saa.2011.07.068 .
Tomić, Zorica, Logar, Vesna P., Babić, Biljana M., Rogan, Jelena R., Makreski, Petre, "Comparison of structural, textural and thermal characteristics of pure and acid treated bentonites from Aleksinac and Petrovac (Serbia)" in Spectrochimica Acta Part A-Molecular and Biomolecular Spectroscopy, 82, no. 1 (2011):389-395,
https://doi.org/10.1016/j.saa.2011.07.068 . .
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