Umićević, Ana

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Authority KeyName Variants
orcid::0000-0001-5251-1070
  • Umićević, Ana (38)
Projects
Investigation of intermetallics and semiconductors and possible application in renewable energy sources Nanostructured multifunctional materials and nanocomposites
Strukturne, dinamičke i spektroskopske karakteristike intermetalika i poluprovodnika Molecular designing of nanoparticles with controlled morphological and physicochemical characteristics and functional materials based on them
Bilateral cooperation between Serbia and France [4510339/2016/09/03 “Inteligent econanomaterials and nanocomposites”] Directed synthesis, structure and properties of multifunctional materials
Geologic and ecotoxicologic research in identification of geopathogen zones of toxic elements in drinking water reservoirs- research into methods and procedures for reduction of biochemical anomalies Optoelectronics nanodimension systems - the rout towards applications
Magnetic and radionuclide labeled nanostructured materials for medical applications Ministry of Education, Science and Technological Development of the Republic of Serbia
NASA: NNX09AV07A National Science Foundation, North Carolina State University [DMR-1523617]
National Science Foundation, North Carolina State University [HRD-1345219] Serbia-Slovenia bilateral research project [BIRS/16/17051]
Slovenian Research Agency [P10125] Bilateral collaboration INCDIE ICPE-CA Bucharest JINR Dubna [04-4-1069-2009/2011, agreement no. 3887-4-09/11/2009]
Czech Ministry of Education, Youth and Sports [1M0512] German Science Foundation (DFG) [DFG: IO 64/7-1]
Nuclear physics, methods and application Physical processes in the synthesis of advanced nanostructured materials
Physics of nanostructured oxide materials and strongly correlated systems Minerals of Serbia: composition, genesis, application and contribution to the environmental sustainability
Lithium-ion batteries and fuel cells - research and development Fizička hemija dinamičkih stanja i struktura neravnotežnih sistema - od monotone do oscilatorne evolucije i haosa
Vodonična energija dobijanje vodonika – gorivne ćelije – izotopski efekti Ministry of Science, Education and Sport of the Republic of Croatia [098-0982904-2941]
NVIDIA Corporation via their GPU Grant Program Office of Basic Energy Sciences, U.S. Department of Energy [DE-Ac02-98CH10886]
Polish Academy of Science, Institute of Physics Belgrade Romanian grant [PNII 12-086/2008]

Author's Bibliography

Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study

Dragojlović, Milijana; Milanović, Igor; Gradišek, Anton; Kurko, Sandra; Mitrić, Miodrag; Umićević, Ana; Radaković, Jana; Batalović, Katarina

(2021)

TY  - JOUR
AU  - Dragojlović, Milijana
AU  - Milanović, Igor
AU  - Gradišek, Anton
AU  - Kurko, Sandra
AU  - Mitrić, Miodrag
AU  - Umićević, Ana
AU  - Radaković, Jana
AU  - Batalović, Katarina
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9087
AB  - LiAlH4 is a promising material for hydrogen storage, having the theoretical gravimetric density of 10.6 wt% H2. In order to decrease the temperature where hydrogen is released, we investigated the catalytic influence of Fe2O3 on LiAlH4 dehydrogenation, as a model case for understanding the effects transition oxide additives have in the catalysis process. Quick mechanochemical synthesis of LiAlH4 + 5 wt% Fe2O3 led to the significant decrease of the hydrogen desorption temperature, and desorption of over 7 wt%H2 in the temperature range 143–154 °C. Density functional theory (DFT)-based calculations with Tran-Blaha modified Becke-Johnson functional (TBmBJ) address the electronic structure of LiAlH4 and Li3AlH6. 57Fe Mössbauer study shows the change in the oxidational state of iron during hydrogen desorption, while the 1H NMR study reveals the presence of paramagnetic species that affect relaxation. The electron transfer from hydrides is discussed as the proposed mechanism of destabilization of LiAlH4 + 5 wt% Fe2O3. © 2021 Hydrogen Energy Publications LLC
T2  - International Journal of Hydrogen Energy
T1  - Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study
VL  - 46
IS  - 24
SP  - 13070
EP  - 13081
DO  - 10.1016/j.ijhydene.2021.01.086
ER  - 
@article{
author = "Dragojlović, Milijana and Milanović, Igor and Gradišek, Anton and Kurko, Sandra and Mitrić, Miodrag and Umićević, Ana and Radaković, Jana and Batalović, Katarina",
year = "2021",
url = "https://vinar.vin.bg.ac.rs/handle/123456789/9087",
abstract = "LiAlH4 is a promising material for hydrogen storage, having the theoretical gravimetric density of 10.6 wt% H2. In order to decrease the temperature where hydrogen is released, we investigated the catalytic influence of Fe2O3 on LiAlH4 dehydrogenation, as a model case for understanding the effects transition oxide additives have in the catalysis process. Quick mechanochemical synthesis of LiAlH4 + 5 wt% Fe2O3 led to the significant decrease of the hydrogen desorption temperature, and desorption of over 7 wt%H2 in the temperature range 143–154 °C. Density functional theory (DFT)-based calculations with Tran-Blaha modified Becke-Johnson functional (TBmBJ) address the electronic structure of LiAlH4 and Li3AlH6. 57Fe Mössbauer study shows the change in the oxidational state of iron during hydrogen desorption, while the 1H NMR study reveals the presence of paramagnetic species that affect relaxation. The electron transfer from hydrides is discussed as the proposed mechanism of destabilization of LiAlH4 + 5 wt% Fe2O3. © 2021 Hydrogen Energy Publications LLC",
journal = "International Journal of Hydrogen Energy",
title = "Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study",
volume = "46",
number = "24",
pages = "13070-13081",
doi = "10.1016/j.ijhydene.2021.01.086"
}
Dragojlović, M., Milanović, I., Gradišek, A., Kurko, S., Mitrić, M., Umićević, A., Radaković, J.,& Batalović, K. (2021). Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study.
International Journal of Hydrogen Energy, 46(24), 13070-13081.
https://doi.org/10.1016/j.ijhydene.2021.01.086
Dragojlović M, Milanović I, Gradišek A, Kurko S, Mitrić M, Umićević A, Radaković J, Batalović K. Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study. International Journal of Hydrogen Energy. 2021;46(24):13070-13081
Dragojlović Milijana, Milanović Igor, Gradišek Anton, Kurko Sandra, Mitrić Miodrag, Umićević Ana, Radaković Jana, Batalović Katarina, "Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study" International Journal of Hydrogen Energy, 46, no. 24 (2021):13070-13081,
https://doi.org/10.1016/j.ijhydene.2021.01.086 .

Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study

Dragojlović, Milijana; Milanović, Igor; Gradišek, Anton; Kurko, Sandra V.; Mitrić, Miodrag; Umićević, Ana; Radaković, Jana; Batalović, Katarina

(2021)

TY  - JOUR
AU  - Dragojlović, Milijana
AU  - Milanović, Igor
AU  - Gradišek, Anton
AU  - Kurko, Sandra V.
AU  - Mitrić, Miodrag
AU  - Umićević, Ana
AU  - Radaković, Jana
AU  - Batalović, Katarina
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9091
AB  - LiAlH4 is a promising material for hydrogen storage, having the theoretical gravimetric density of 10.6 wt% H2. In order to decrease the temperature where hydrogen is released, we investigated the catalytic influence of Fe2O3 on LiAlH4 dehydrogenation, as a model case for understanding the effects transition oxide additives have in the catalysis process. Quick mechanochemical synthesis of LiAlH4 + 5 wt% Fe2O3 led to the significant decrease of the hydrogen desorption temperature, and desorption of over 7 wt%H2 in the temperature range 143–154 °C. Density functional theory (DFT)-based calculations with Tran-Blaha modified Becke-Johnson functional (TBmBJ) address the electronic structure of LiAlH4 and Li3AlH6. 57Fe Mössbauer study shows the change in the oxidational state of iron during hydrogen desorption, while the 1H NMR study reveals the presence of paramagnetic species that affect relaxation. The electron transfer from hydrides is discussed as the proposed mechanism of destabilization of LiAlH4 + 5 wt% Fe2O3. © 2021 Hydrogen Energy Publications LLC
T2  - International Journal of Hydrogen Energy
T1  - Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study
VL  - 46
IS  - 24
SP  - 13070
EP  - 13081
DO  - 10.1016/j.ijhydene.2021.01.086
ER  - 
@article{
author = "Dragojlović, Milijana and Milanović, Igor and Gradišek, Anton and Kurko, Sandra V. and Mitrić, Miodrag and Umićević, Ana and Radaković, Jana and Batalović, Katarina",
year = "2021",
url = "https://vinar.vin.bg.ac.rs/handle/123456789/9091",
abstract = "LiAlH4 is a promising material for hydrogen storage, having the theoretical gravimetric density of 10.6 wt% H2. In order to decrease the temperature where hydrogen is released, we investigated the catalytic influence of Fe2O3 on LiAlH4 dehydrogenation, as a model case for understanding the effects transition oxide additives have in the catalysis process. Quick mechanochemical synthesis of LiAlH4 + 5 wt% Fe2O3 led to the significant decrease of the hydrogen desorption temperature, and desorption of over 7 wt%H2 in the temperature range 143–154 °C. Density functional theory (DFT)-based calculations with Tran-Blaha modified Becke-Johnson functional (TBmBJ) address the electronic structure of LiAlH4 and Li3AlH6. 57Fe Mössbauer study shows the change in the oxidational state of iron during hydrogen desorption, while the 1H NMR study reveals the presence of paramagnetic species that affect relaxation. The electron transfer from hydrides is discussed as the proposed mechanism of destabilization of LiAlH4 + 5 wt% Fe2O3. © 2021 Hydrogen Energy Publications LLC",
journal = "International Journal of Hydrogen Energy",
title = "Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study",
volume = "46",
number = "24",
pages = "13070-13081",
doi = "10.1016/j.ijhydene.2021.01.086"
}
Dragojlović, M., Milanović, I., Gradišek, A., Kurko, S. V., Mitrić, M., Umićević, A., Radaković, J.,& Batalović, K. (2021). Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study.
International Journal of Hydrogen Energy, 46(24), 13070-13081.
https://doi.org/10.1016/j.ijhydene.2021.01.086
Dragojlović M, Milanović I, Gradišek A, Kurko SV, Mitrić M, Umićević A, Radaković J, Batalović K. Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study. International Journal of Hydrogen Energy. 2021;46(24):13070-13081
Dragojlović Milijana, Milanović Igor, Gradišek Anton, Kurko Sandra V., Mitrić Miodrag, Umićević Ana, Radaković Jana, Batalović Katarina, "Mechanochemical modification of LiAlH4 with Fe2O3 - A combined DFT and experimental study" International Journal of Hydrogen Energy, 46, no. 24 (2021):13070-13081,
https://doi.org/10.1016/j.ijhydene.2021.01.086 .

Ab initio calculations of the optical and electronic properties of Bi2WO6 doped with Mo, Cr, Fe, and Zn on the W–lattice site

Koteski, Vasil J.; Belošević-Čavor, Jelena; Ivanovski, Valentin N.; Umićević, Ana; Toprek, Dragan

(2020)

TY  - JOUR
AU  - Koteski, Vasil J.
AU  - Belošević-Čavor, Jelena
AU  - Ivanovski, Valentin N.
AU  - Umićević, Ana
AU  - Toprek, Dragan
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8889
AB  - Substitutionally doped Bi2W1-xMxO6 (M = Mo, Cr, Fe, Zn; x = 0.125, 0,25, 0.5) is investigated using the density functional theory (DFT). For all the investigated transition metal dopants, the optical properties in the visible light range are improved over the undoped Bi2WO6. Irrespective of concentration, the lattice relaxation around the dopants is constrained to the first coordination shell. Mo, Fe, and Cr introduce localized defect states in the band gap, contributing to band gap narrowing. The localized states are hybridized between the impurity d–bands and host W 5d–and O 2p–states. Zn facilitates the reduction of the band gap by inducing a shift of the states near the top of the valence band toward higher energies. Our results suggest that Zn doping on the W lattice site may improve the photocatalytic properties of Bi2WO6 more than the other dopants.
T2  - Applied Surface Science
T1  - Ab initio calculations of the optical and electronic properties of Bi2WO6 doped with Mo, Cr, Fe, and Zn on the W–lattice site
VL  - 515
SP  - 146036
DO  - 10.1016/j.apsusc.2020.146036
ER  - 
@article{
author = "Koteski, Vasil J. and Belošević-Čavor, Jelena and Ivanovski, Valentin N. and Umićević, Ana and Toprek, Dragan",
year = "2020",
url = "https://vinar.vin.bg.ac.rs/handle/123456789/8889",
abstract = "Substitutionally doped Bi2W1-xMxO6 (M = Mo, Cr, Fe, Zn; x = 0.125, 0,25, 0.5) is investigated using the density functional theory (DFT). For all the investigated transition metal dopants, the optical properties in the visible light range are improved over the undoped Bi2WO6. Irrespective of concentration, the lattice relaxation around the dopants is constrained to the first coordination shell. Mo, Fe, and Cr introduce localized defect states in the band gap, contributing to band gap narrowing. The localized states are hybridized between the impurity d–bands and host W 5d–and O 2p–states. Zn facilitates the reduction of the band gap by inducing a shift of the states near the top of the valence band toward higher energies. Our results suggest that Zn doping on the W lattice site may improve the photocatalytic properties of Bi2WO6 more than the other dopants.",
journal = "Applied Surface Science",
title = "Ab initio calculations of the optical and electronic properties of Bi2WO6 doped with Mo, Cr, Fe, and Zn on the W–lattice site",
volume = "515",
pages = "146036",
doi = "10.1016/j.apsusc.2020.146036"
}
Koteski, V. J., Belošević-Čavor, J., Ivanovski, V. N., Umićević, A.,& Toprek, D. (2020). Ab initio calculations of the optical and electronic properties of Bi2WO6 doped with Mo, Cr, Fe, and Zn on the W–lattice site.
Applied Surface Science, 515, 146036.
https://doi.org/10.1016/j.apsusc.2020.146036
Koteski VJ, Belošević-Čavor J, Ivanovski VN, Umićević A, Toprek D. Ab initio calculations of the optical and electronic properties of Bi2WO6 doped with Mo, Cr, Fe, and Zn on the W–lattice site. Applied Surface Science. 2020;515:146036
Koteski Vasil J., Belošević-Čavor Jelena, Ivanovski Valentin N., Umićević Ana, Toprek Dragan, "Ab initio calculations of the optical and electronic properties of Bi2WO6 doped with Mo, Cr, Fe, and Zn on the W–lattice site" Applied Surface Science, 515 (2020):146036,
https://doi.org/10.1016/j.apsusc.2020.146036 .
3
2
2

Characterization of LiFePO4 samples obtained by pulse combustion under various conditions of synthesis

Lazarević, Zorica Ž.; Križan, Gregor; Križan, Janez; Milutinović, Aleksandra N.; Ivanovski, Valentin N.; Mitrić, Miodrag; Gilić, Martina; Umićević, Ana; Kuryliszyn-Kudelska, Izabela; Romčević, Nebojša Ž.

(2019)

TY  - JOUR
AU  - Lazarević, Zorica Ž.
AU  - Križan, Gregor
AU  - Križan, Janez
AU  - Milutinović, Aleksandra N.
AU  - Ivanovski, Valentin N.
AU  - Mitrić, Miodrag
AU  - Gilić, Martina
AU  - Umićević, Ana
AU  - Kuryliszyn-Kudelska, Izabela
AU  - Romčević, Nebojša Ž.
PY  - 2019
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8501
AB  - Lithium iron phosphate (LiFePO4, LFP) is one of the widely used cathode materials for rechargeable lithium ion batteries. LFP batteries are widely used for electric vehicles and backup power due to their important advantages such as low cost, lifetime, efficiency, and reliability. There are still several technical challenges that need to be addressed: The increase of energy density or further reduction of their final cost. This paper concerned with the characterization of carbon coated LiFePO4 nanopowder cathode materials produced under different conditions by pulse combustion for providing energy to the reactor for the synthesis. The reactor was built according to the principles of the thermoacoustic burner on the basis of the Helmholtz resonator. The investigated nanopowders are synthesized by complete and incomplete combustion and calcined at 700 °C. The obtained samples were characterized by X-ray diffraction, Fourier transform infrared, Raman, and Mössbauer spectroscopy. Observed low-Temperature magnetic phase transitions definitively identified the crystal phases. The morphology of samples was controlled by scanning electron microscopy. The aim of this work is to show that it is possible to achieve a desired crystal phase by pulse combustion in a relatively cheap and fast way. The extremely rapid synthesis of almost pure phase material is possible due to the reduction in size of interacting particles and to an enormous number of collisions between them as a result of strong turbulent flow associated with explosive combustion. © 2019 Author(s).
T2  - Journal of Applied Physics
T1  - Characterization of LiFePO4 samples obtained by pulse combustion under various conditions of synthesis
VL  - 126
IS  - 8
SP  - 085109
DO  - 10.1063/1.5100358
ER  - 
@article{
author = "Lazarević, Zorica Ž. and Križan, Gregor and Križan, Janez and Milutinović, Aleksandra N. and Ivanovski, Valentin N. and Mitrić, Miodrag and Gilić, Martina and Umićević, Ana and Kuryliszyn-Kudelska, Izabela and Romčević, Nebojša Ž.",
year = "2019",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/8501",
abstract = "Lithium iron phosphate (LiFePO4, LFP) is one of the widely used cathode materials for rechargeable lithium ion batteries. LFP batteries are widely used for electric vehicles and backup power due to their important advantages such as low cost, lifetime, efficiency, and reliability. There are still several technical challenges that need to be addressed: The increase of energy density or further reduction of their final cost. This paper concerned with the characterization of carbon coated LiFePO4 nanopowder cathode materials produced under different conditions by pulse combustion for providing energy to the reactor for the synthesis. The reactor was built according to the principles of the thermoacoustic burner on the basis of the Helmholtz resonator. The investigated nanopowders are synthesized by complete and incomplete combustion and calcined at 700 °C. The obtained samples were characterized by X-ray diffraction, Fourier transform infrared, Raman, and Mössbauer spectroscopy. Observed low-Temperature magnetic phase transitions definitively identified the crystal phases. The morphology of samples was controlled by scanning electron microscopy. The aim of this work is to show that it is possible to achieve a desired crystal phase by pulse combustion in a relatively cheap and fast way. The extremely rapid synthesis of almost pure phase material is possible due to the reduction in size of interacting particles and to an enormous number of collisions between them as a result of strong turbulent flow associated with explosive combustion. © 2019 Author(s).",
journal = "Journal of Applied Physics",
title = "Characterization of LiFePO4 samples obtained by pulse combustion under various conditions of synthesis",
volume = "126",
number = "8",
pages = "085109",
doi = "10.1063/1.5100358"
}
Lazarević, Z. Ž., Križan, G., Križan, J., Milutinović, A. N., Ivanovski, V. N., Mitrić, M., Gilić, M., Umićević, A., Kuryliszyn-Kudelska, I.,& Romčević, N. Ž. (2019). Characterization of LiFePO4 samples obtained by pulse combustion under various conditions of synthesis.
Journal of Applied Physics, 126(8), 085109.
https://doi.org/10.1063/1.5100358
Lazarević ZŽ, Križan G, Križan J, Milutinović AN, Ivanovski VN, Mitrić M, Gilić M, Umićević A, Kuryliszyn-Kudelska I, Romčević NŽ. Characterization of LiFePO4 samples obtained by pulse combustion under various conditions of synthesis. Journal of Applied Physics. 2019;126(8):085109
Lazarević Zorica Ž., Križan Gregor, Križan Janez, Milutinović Aleksandra N., Ivanovski Valentin N., Mitrić Miodrag, Gilić Martina, Umićević Ana, Kuryliszyn-Kudelska Izabela, Romčević Nebojša Ž., "Characterization of LiFePO4 samples obtained by pulse combustion under various conditions of synthesis" Journal of Applied Physics, 126, no. 8 (2019):085109,
https://doi.org/10.1063/1.5100358 .

Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal

Rusmirović, Jelena D.; Obradović, Nina; Perendija, Jovana; Umićević, Ana; Kapidžić, Ana; Vlahović, Branislav; Pavlović, Vera P.; Marinković, Aleksandar D.; Pavlović, Vladimir B.

(2019)

TY  - JOUR
AU  - Rusmirović, Jelena D.
AU  - Obradović, Nina
AU  - Perendija, Jovana
AU  - Umićević, Ana
AU  - Kapidžić, Ana
AU  - Vlahović, Branislav
AU  - Pavlović, Vera P.
AU  - Marinković, Aleksandar D.
AU  - Pavlović, Vladimir B.
PY  - 2019
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8096
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, Mössbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456 mg g -1 for WL-?-APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382 mg g -1 for Cd 2+ , Ni 2+ , 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. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
T2  - Environmental Science and Pollution Research
T1  - Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal
VL  - 26
IS  - 12
SP  - 12379
EP  - 12398
DO  - 10.1007/s11356-019-04625-0
ER  - 
@article{
author = "Rusmirović, Jelena D. and Obradović, Nina and Perendija, Jovana and Umićević, Ana and Kapidžić, Ana and Vlahović, Branislav and Pavlović, Vera P. and Marinković, Aleksandar D. and Pavlović, Vladimir B.",
year = "2019",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/8096",
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, Mössbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456 mg g -1 for WL-?-APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382 mg g -1 for Cd 2+ , Ni 2+ , 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. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.",
journal = "Environmental Science and Pollution Research",
title = "Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal",
volume = "26",
number = "12",
pages = "12379-12398",
doi = "10.1007/s11356-019-04625-0"
}
Rusmirović, J. D., Obradović, N., Perendija, J., Umićević, A., Kapidžić, A., Vlahović, B., Pavlović, V. P., Marinković, A. D.,& Pavlović, V. B. (2019). Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal.
Environmental Science and Pollution Research, 26(12), 12379-12398.
https://doi.org/10.1007/s11356-019-04625-0
Rusmirović JD, Obradović N, Perendija J, Umićević A, Kapidžić A, Vlahović B, Pavlović VP, Marinković AD, Pavlović VB. Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal. Environmental Science and Pollution Research. 2019;26(12):12379-12398
Rusmirović Jelena D., Obradović Nina, Perendija Jovana, Umićević Ana, Kapidžić Ana, Vlahović Branislav, Pavlović Vera P., Marinković Aleksandar D., Pavlović Vladimir B., "Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal" Environmental Science and Pollution Research, 26, no. 12 (2019):12379-12398,
https://doi.org/10.1007/s11356-019-04625-0 .
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Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal

Rusmirović, Jelena D.; Obradović, Nina; Perendija, Jovana; Umićević, Ana; Kapidžić, Ana; Vlahović, Branislav; Pavlović, Vera P.; Marinković, Aleksandar D.; Pavlović, Vladimir B.

(2019)

TY  - JOUR
AU  - Rusmirović, Jelena D.
AU  - Obradović, Nina
AU  - Perendija, Jovana
AU  - Umićević, Ana
AU  - Kapidžić, Ana
AU  - Vlahović, Branislav
AU  - Pavlović, Vera P.
AU  - Marinković, Aleksandar D.
AU  - Pavlović, Vladimir B.
PY  - 2019
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8101
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-γ-APS/MG adsorbents, respectively. The structure/properties of MG functionalized WL was confirmed by applying FTIR, Raman, XRD, Mössbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456 mg g−1 for WL-γ-APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382 mg g−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-γ-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-γ-APS.
T2  - Environmental Science and Pollution Research
T1  - Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal
VL  - 26
IS  - 12
SP  - 12379
EP  - 12398
DO  - 10.1007/s11356-019-04625-0
ER  - 
@article{
author = "Rusmirović, Jelena D. and Obradović, Nina and Perendija, Jovana and Umićević, Ana and Kapidžić, Ana and Vlahović, Branislav and Pavlović, Vera P. and Marinković, Aleksandar D. and Pavlović, Vladimir B.",
year = "2019",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/8101",
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-γ-APS/MG adsorbents, respectively. The structure/properties of MG functionalized WL was confirmed by applying FTIR, Raman, XRD, Mössbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456 mg g−1 for WL-γ-APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382 mg g−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-γ-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-γ-APS.",
journal = "Environmental Science and Pollution Research",
title = "Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal",
volume = "26",
number = "12",
pages = "12379-12398",
doi = "10.1007/s11356-019-04625-0"
}
Rusmirović, J. D., Obradović, N., Perendija, J., Umićević, A., Kapidžić, A., Vlahović, B., Pavlović, V. P., Marinković, A. D.,& Pavlović, V. B. (2019). Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal.
Environmental Science and Pollution Research, 26(12), 12379-12398.
https://doi.org/10.1007/s11356-019-04625-0
Rusmirović JD, Obradović N, Perendija J, Umićević A, Kapidžić A, Vlahović B, Pavlović VP, Marinković AD, Pavlović VB. Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal. Environmental Science and Pollution Research. 2019;26(12):12379-12398
Rusmirović Jelena D., Obradović Nina, Perendija Jovana, Umićević Ana, Kapidžić Ana, Vlahović Branislav, Pavlović Vera P., Marinković Aleksandar D., Pavlović Vladimir B., "Controllable synthesis of Fe3O4-wollastonite adsorbents for efficient heavy metal ions/oxyanions removal" Environmental Science and Pollution Research, 26, no. 12 (2019):12379-12398,
https://doi.org/10.1007/s11356-019-04625-0 .
1
4
6
6

A study of defect structures in Fe-alloyed ZnO: Morphology, magnetism, and hyperfine interactions

Ivanovski, Valentin N.; Belošević-Čavor, Jelena; Rajić, Vladimir; Umićević, Ana; Marković, Smilja; Kusigerski, Vladan; Mitrić, Miodrag; Koteski, Vasil J.

(2019)

TY  - JOUR
AU  - Ivanovski, Valentin N.
AU  - Belošević-Čavor, Jelena
AU  - Rajić, Vladimir
AU  - Umićević, Ana
AU  - Marković, Smilja
AU  - Kusigerski, Vladan
AU  - Mitrić, Miodrag
AU  - Koteski, Vasil J.
PY  - 2019
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/8515
AB  - In order to study the effect of Fe cation substitution on the local structure, defect formation, and hyperfine interactions in ZnO, Mössbauer spectroscopy measurements of the microwave processed Zn 1 - x Fe x O (x = 0.05, 0.10, 0.15, and 0.20) nanoparticles, together with ab initio calculations, were performed. Complementary information on the distribution of particle size and morphology, as well as magnetic properties, were obtained by X-ray diffraction, transmission electron microscopy, and squid-magnetometry. The selected model for analyzing the Mössbauer spectra of our samples is a distribution of quadrupole splittings. The fitting model with two Lorentz doublets was rejected due to its failure to include larger doublets. The Fe 3 + ions do not yield magnetic ordering in the samples at room temperature. The results from first-principles calculations confirm that the major component of the Mössbauer spectra corresponds to the Fe-alloyed ZnO with Zn vacancy in the next nearest neighbor environment. The magnetic measurements are consistent with the description of the distribution of iron ions over the randomly formed clusters in the ZnO host lattice. While at room temperature all the samples are paramagnetic, magnetic interactions cause a transition into a cluster spin-glass state at low temperatures. © 2019 Author(s).
T2  - Journal of Applied Physics
T1  - A study of defect structures in Fe-alloyed ZnO: Morphology, magnetism, and hyperfine interactions
VL  - 126
IS  - 12
SP  - 125703
DO  - 10.1063/1.5095837
ER  - 
@article{
author = "Ivanovski, Valentin N. and Belošević-Čavor, Jelena and Rajić, Vladimir and Umićević, Ana and Marković, Smilja and Kusigerski, Vladan and Mitrić, Miodrag and Koteski, Vasil J.",
year = "2019",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/8515",
abstract = "In order to study the effect of Fe cation substitution on the local structure, defect formation, and hyperfine interactions in ZnO, Mössbauer spectroscopy measurements of the microwave processed Zn 1 - x Fe x O (x = 0.05, 0.10, 0.15, and 0.20) nanoparticles, together with ab initio calculations, were performed. Complementary information on the distribution of particle size and morphology, as well as magnetic properties, were obtained by X-ray diffraction, transmission electron microscopy, and squid-magnetometry. The selected model for analyzing the Mössbauer spectra of our samples is a distribution of quadrupole splittings. The fitting model with two Lorentz doublets was rejected due to its failure to include larger doublets. The Fe 3 + ions do not yield magnetic ordering in the samples at room temperature. The results from first-principles calculations confirm that the major component of the Mössbauer spectra corresponds to the Fe-alloyed ZnO with Zn vacancy in the next nearest neighbor environment. The magnetic measurements are consistent with the description of the distribution of iron ions over the randomly formed clusters in the ZnO host lattice. While at room temperature all the samples are paramagnetic, magnetic interactions cause a transition into a cluster spin-glass state at low temperatures. © 2019 Author(s).",
journal = "Journal of Applied Physics",
title = "A study of defect structures in Fe-alloyed ZnO: Morphology, magnetism, and hyperfine interactions",
volume = "126",
number = "12",
pages = "125703",
doi = "10.1063/1.5095837"
}
Ivanovski, V. N., Belošević-Čavor, J., Rajić, V., Umićević, A., Marković, S., Kusigerski, V., Mitrić, M.,& Koteski, V. J. (2019). A study of defect structures in Fe-alloyed ZnO: Morphology, magnetism, and hyperfine interactions.
Journal of Applied Physics, 126(12), 125703.
https://doi.org/10.1063/1.5095837
Ivanovski VN, Belošević-Čavor J, Rajić V, Umićević A, Marković S, Kusigerski V, Mitrić M, Koteski VJ. A study of defect structures in Fe-alloyed ZnO: Morphology, magnetism, and hyperfine interactions. Journal of Applied Physics. 2019;126(12):125703
Ivanovski Valentin N., Belošević-Čavor Jelena, Rajić Vladimir, Umićević Ana, Marković Smilja, Kusigerski Vladan, Mitrić Miodrag, Koteski Vasil J., "A study of defect structures in Fe-alloyed ZnO: Morphology, magnetism, and hyperfine interactions" Journal of Applied Physics, 126, no. 12 (2019):125703,
https://doi.org/10.1063/1.5095837 .
4
3
3

Effect of 5d transition metals doping on the photocatalytic properties of rutile TiO 2

Belošević-Čavor, Jelena; Koteski, Vasil J.; Umićević, Ana; Ivanovski, Valentin N.

(2018)

TY  - JOUR
AU  - Belošević-Čavor, Jelena
AU  - Koteski, Vasil J.
AU  - Umićević, Ana
AU  - Ivanovski, Valentin N.
PY  - 2018
UR  - http://linkinghub.elsevier.com/retrieve/pii/S0927025618303306
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/7700
AB  - Density functional theory (DFT) calculations were performed to address the effects of 5d transition metals (TM) doping on the electronic structure properties of rutile TiO2, using both the modified Becke-Johnson (mBJ) and on-site hybrid functional. The calculations show that there is a reduction of band gap in almost all the investigated cases, except when TiO2is doped with Ta. Some of the investigated systems (Re, W, Os, Ir) exhibit pronounced spin polarization, mainly arising from the TM atoms. In addition, a large increase of band gap is observed, when switching from a 24-atoms to 48-atoms supercell, while further enlarging the supercell size doesn't affect the band gap significantly. Among the investigated transition metals, Pt and Ir are the best candidates for improving the photocatalytic properties of rutile TiO2through substitutional doping.
T2  - Computational Materials Science
T1  - Effect of 5d transition metals doping on the photocatalytic properties of rutile TiO 2
VL  - 151
SP  - 328
EP  - 337
DO  - 10.1016/j.commatsci.2018.05.022
ER  - 
@article{
author = "Belošević-Čavor, Jelena and Koteski, Vasil J. and Umićević, Ana and Ivanovski, Valentin N.",
year = "2018",
url = "http://linkinghub.elsevier.com/retrieve/pii/S0927025618303306, http://vinar.vin.bg.ac.rs/handle/123456789/7700",
abstract = "Density functional theory (DFT) calculations were performed to address the effects of 5d transition metals (TM) doping on the electronic structure properties of rutile TiO2, using both the modified Becke-Johnson (mBJ) and on-site hybrid functional. The calculations show that there is a reduction of band gap in almost all the investigated cases, except when TiO2is doped with Ta. Some of the investigated systems (Re, W, Os, Ir) exhibit pronounced spin polarization, mainly arising from the TM atoms. In addition, a large increase of band gap is observed, when switching from a 24-atoms to 48-atoms supercell, while further enlarging the supercell size doesn't affect the band gap significantly. Among the investigated transition metals, Pt and Ir are the best candidates for improving the photocatalytic properties of rutile TiO2through substitutional doping.",
journal = "Computational Materials Science",
title = "Effect of 5d transition metals doping on the photocatalytic properties of rutile TiO 2",
volume = "151",
pages = "328-337",
doi = "10.1016/j.commatsci.2018.05.022"
}
Belošević-Čavor, J., Koteski, V. J., Umićević, A.,& Ivanovski, V. N. (2018). Effect of 5d transition metals doping on the photocatalytic properties of rutile TiO 2.
Computational Materials Science, 151, 328-337.
https://doi.org/10.1016/j.commatsci.2018.05.022
Belošević-Čavor J, Koteski VJ, Umićević A, Ivanovski VN. Effect of 5d transition metals doping on the photocatalytic properties of rutile TiO 2. Computational Materials Science. 2018;151:328-337
Belošević-Čavor Jelena, Koteski Vasil J., Umićević Ana, Ivanovski Valentin N., "Effect of 5d transition metals doping on the photocatalytic properties of rutile TiO 2" Computational Materials Science, 151 (2018):328-337,
https://doi.org/10.1016/j.commatsci.2018.05.022 .
6
6
6

Improving the photocatalytic properties of anatase TiO2(101) surface by co-doping with Cu and N: Ab initio study

Koteski, Vasil J.; Belošević-Čavor, Jelena; Umićević, Ana; Ivanovski, Valentin N.; Toprek, Dragan

(2017)

TY  - JOUR
AU  - Koteski, Vasil J.
AU  - Belošević-Čavor, Jelena
AU  - Umićević, Ana
AU  - Ivanovski, Valentin N.
AU  - Toprek, Dragan
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1721
AB  - Substitutionally and interstitially Cu/Nco-doped anatase TiO2(101) surface is investigated by using density functional theory (DFT) calculations. The results suggest improved visible light photocatalytic activity over undoped anatase TiO2. Sizable lattice relaxation around the dopants is observed, followed by a formation of N-O bond. Depending on the local arrangement of atoms, localized states above the valence band maximum, deep into the band gap, and below the conduction band minimum are found. In addition, our calculation also predict band gap narrowing. The hybridization of the Cu 3d and N 2p states within the band gap and the other electronic and optical properties suggest a synergistic effect of the dopants in the enhancement of the visible light absorption on the (101) anatase surface. (C) 2017 Elsevier B.V. All rights reserved.
T2  - Applied Surface Science
T1  - Improving the photocatalytic properties of anatase TiO2(101) surface by co-doping with Cu and N: Ab initio study
VL  - 425
SP  - 1095
EP  - 1100
DO  - 10.1016/j.apsusc.2017.07.064
ER  - 
@article{
author = "Koteski, Vasil J. and Belošević-Čavor, Jelena and Umićević, Ana and Ivanovski, Valentin N. and Toprek, Dragan",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1721",
abstract = "Substitutionally and interstitially Cu/Nco-doped anatase TiO2(101) surface is investigated by using density functional theory (DFT) calculations. The results suggest improved visible light photocatalytic activity over undoped anatase TiO2. Sizable lattice relaxation around the dopants is observed, followed by a formation of N-O bond. Depending on the local arrangement of atoms, localized states above the valence band maximum, deep into the band gap, and below the conduction band minimum are found. In addition, our calculation also predict band gap narrowing. The hybridization of the Cu 3d and N 2p states within the band gap and the other electronic and optical properties suggest a synergistic effect of the dopants in the enhancement of the visible light absorption on the (101) anatase surface. (C) 2017 Elsevier B.V. All rights reserved.",
journal = "Applied Surface Science",
title = "Improving the photocatalytic properties of anatase TiO2(101) surface by co-doping with Cu and N: Ab initio study",
volume = "425",
pages = "1095-1100",
doi = "10.1016/j.apsusc.2017.07.064"
}
Koteski, V. J., Belošević-Čavor, J., Umićević, A., Ivanovski, V. N.,& Toprek, D. (2017). Improving the photocatalytic properties of anatase TiO2(101) surface by co-doping with Cu and N: Ab initio study.
Applied Surface Science, 425, 1095-1100.
https://doi.org/10.1016/j.apsusc.2017.07.064
Koteski VJ, Belošević-Čavor J, Umićević A, Ivanovski VN, Toprek D. Improving the photocatalytic properties of anatase TiO2(101) surface by co-doping with Cu and N: Ab initio study. Applied Surface Science. 2017;425:1095-1100
Koteski Vasil J., Belošević-Čavor Jelena, Umićević Ana, Ivanovski Valentin N., Toprek Dragan, "Improving the photocatalytic properties of anatase TiO2(101) surface by co-doping with Cu and N: Ab initio study" Applied Surface Science, 425 (2017):1095-1100,
https://doi.org/10.1016/j.apsusc.2017.07.064 .
6
5
7

Ab initio study of electronic and optical properties of Fe doped anatase TiO2 (101) surface

Toprek, Dragan; Koteski, Vasil J.; Belošević-Čavor, Jelena; Ivanovski, Valentin N.; Umićević, Ana

(2017)

TY  - JOUR
AU  - Toprek, Dragan
AU  - Koteski, Vasil J.
AU  - Belošević-Čavor, Jelena
AU  - Ivanovski, Valentin N.
AU  - Umićević, Ana
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1834
AB  - In this paper we investigated the effects of Fe-doping of the anatase TiO2 (1 0 1) surface on the crystal structure, electronic and optical properties, and impurity formation energy by means of density functional theory (DFT). The calculations were performed by the SIESTA DFT code and were carried out by using Troullier-Martins pseudopotentials for the 12-electron valence configuration (3s(2)3p(6)3d(2)4s(2)) of Ti atom, 6-electron valence configuration (2s(2)p(4)) of O atom and 8-electron valence configuration (3d(6)4s(2)) of Fe atom. We used a double- zeta basis set including polarization functions. All calculations were spin-polarized. The mechanism of narrowing the band gap and increasing the photocatalytic activity in the visible light region, of the doped TiO2 is discussed by investigating the density of state. The band gap decreases as the concentration of the dopant increases. The Partial Density of States (PDOS) is not the same in the case of spin-up state or spin-down state. Enhanced optical absorption, for light polarized in the z direction (parallel to the surface normal) is clearly observed for Fe doped as compared to the pure anatase TiO2 and the optical absorption is found to increase with the increase in the Fe concentration. The DFT results indicate that the source of the increasing photocatalytic activity in the visible light region of the Fe doped material is due to the introduction of additional electronic states within the band gap. Since the Fe atoms are more stable in Ti substitutional lattice positions for the entire range of Fermi energy E-F over the band gap, only this substitutional position is considered. We hope that our results will highlight a route to improved electronic and optical properties of anatase TiO2 for industrial applications. (C) 2017 Elsevier B.V. All rights reserved.
T2  - Computational and Theoretical Chemistry
T1  - Ab initio study of electronic and optical properties of Fe doped anatase TiO2 (101) surface
VL  - 1120
SP  - 17
EP  - 23
DO  - 10.1016/j.comptc.2017.09.024
ER  - 
@article{
author = "Toprek, Dragan and Koteski, Vasil J. and Belošević-Čavor, Jelena and Ivanovski, Valentin N. and Umićević, Ana",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1834",
abstract = "In this paper we investigated the effects of Fe-doping of the anatase TiO2 (1 0 1) surface on the crystal structure, electronic and optical properties, and impurity formation energy by means of density functional theory (DFT). The calculations were performed by the SIESTA DFT code and were carried out by using Troullier-Martins pseudopotentials for the 12-electron valence configuration (3s(2)3p(6)3d(2)4s(2)) of Ti atom, 6-electron valence configuration (2s(2)p(4)) of O atom and 8-electron valence configuration (3d(6)4s(2)) of Fe atom. We used a double- zeta basis set including polarization functions. All calculations were spin-polarized. The mechanism of narrowing the band gap and increasing the photocatalytic activity in the visible light region, of the doped TiO2 is discussed by investigating the density of state. The band gap decreases as the concentration of the dopant increases. The Partial Density of States (PDOS) is not the same in the case of spin-up state or spin-down state. Enhanced optical absorption, for light polarized in the z direction (parallel to the surface normal) is clearly observed for Fe doped as compared to the pure anatase TiO2 and the optical absorption is found to increase with the increase in the Fe concentration. The DFT results indicate that the source of the increasing photocatalytic activity in the visible light region of the Fe doped material is due to the introduction of additional electronic states within the band gap. Since the Fe atoms are more stable in Ti substitutional lattice positions for the entire range of Fermi energy E-F over the band gap, only this substitutional position is considered. We hope that our results will highlight a route to improved electronic and optical properties of anatase TiO2 for industrial applications. (C) 2017 Elsevier B.V. All rights reserved.",
journal = "Computational and Theoretical Chemistry",
title = "Ab initio study of electronic and optical properties of Fe doped anatase TiO2 (101) surface",
volume = "1120",
pages = "17-23",
doi = "10.1016/j.comptc.2017.09.024"
}
Toprek, D., Koteski, V. J., Belošević-Čavor, J., Ivanovski, V. N.,& Umićević, A. (2017). Ab initio study of electronic and optical properties of Fe doped anatase TiO2 (101) surface.
Computational and Theoretical Chemistry, 1120, 17-23.
https://doi.org/10.1016/j.comptc.2017.09.024
Toprek D, Koteski VJ, Belošević-Čavor J, Ivanovski VN, Umićević A. Ab initio study of electronic and optical properties of Fe doped anatase TiO2 (101) surface. Computational and Theoretical Chemistry. 2017;1120:17-23
Toprek Dragan, Koteski Vasil J., Belošević-Čavor Jelena, Ivanovski Valentin N., Umićević Ana, "Ab initio study of electronic and optical properties of Fe doped anatase TiO2 (101) surface" Computational and Theoretical Chemistry, 1120 (2017):17-23,
https://doi.org/10.1016/j.comptc.2017.09.024 .
5
5
6

Yttrium Orthoferrite Powder Obtained by the Mechanochemical Synthesis

Lazarević, Zorica Ž.; Jovalekic, Cedomir; Gilic, Martina; Ivanovski, Valentin N.; Umićević, Ana; Sekulić, Dalibor L.; Romčević, Nebojša Ž.

(2017)

TY  - JOUR
AU  - Lazarević, Zorica Ž.
AU  - Jovalekic, Cedomir
AU  - Gilic, Martina
AU  - Ivanovski, Valentin N.
AU  - Umićević, Ana
AU  - Sekulić, Dalibor L.
AU  - Romčević, Nebojša Ž.
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1778
AB  - Yttrium orthoferrite (YFeO3) powder was prepared by a mechanochemical synthesis from a mixture of Y2O3 and alpha-Fe2O3 powders in a planetary ball mill for 2.5 h. The obtained YFeO3 powder sample was characterized by X-ray diffraction (XRD), Raman and infrared spectroscopy. The average crystallite size calculated by the Scherrer equation was 12 nm. The Mossbauer spectroscopy at room temperature confirms the superparamagnetic character of YFeO3 orthoferrite sample.
T2  - Science of Sintering
T1  - Yttrium Orthoferrite Powder Obtained by the Mechanochemical Synthesis
VL  - 49
IS  - 3
SP  - 277
EP  - 284
DO  - 10.2298/SOS1703277L
ER  - 
@article{
author = "Lazarević, Zorica Ž. and Jovalekic, Cedomir and Gilic, Martina and Ivanovski, Valentin N. and Umićević, Ana and Sekulić, Dalibor L. and Romčević, Nebojša Ž.",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1778",
abstract = "Yttrium orthoferrite (YFeO3) powder was prepared by a mechanochemical synthesis from a mixture of Y2O3 and alpha-Fe2O3 powders in a planetary ball mill for 2.5 h. The obtained YFeO3 powder sample was characterized by X-ray diffraction (XRD), Raman and infrared spectroscopy. The average crystallite size calculated by the Scherrer equation was 12 nm. The Mossbauer spectroscopy at room temperature confirms the superparamagnetic character of YFeO3 orthoferrite sample.",
journal = "Science of Sintering",
title = "Yttrium Orthoferrite Powder Obtained by the Mechanochemical Synthesis",
volume = "49",
number = "3",
pages = "277-284",
doi = "10.2298/SOS1703277L"
}
Lazarević, Z. Ž., Jovalekic, C., Gilic, M., Ivanovski, V. N., Umićević, A., Sekulić, D. L.,& Romčević, N. Ž. (2017). Yttrium Orthoferrite Powder Obtained by the Mechanochemical Synthesis.
Science of Sintering, 49(3), 277-284.
https://doi.org/10.2298/SOS1703277L
Lazarević ZŽ, Jovalekic C, Gilic M, Ivanovski VN, Umićević A, Sekulić DL, Romčević NŽ. Yttrium Orthoferrite Powder Obtained by the Mechanochemical Synthesis. Science of Sintering. 2017;49(3):277-284
Lazarević Zorica Ž., Jovalekic Cedomir, Gilic Martina, Ivanovski Valentin N., Umićević Ana, Sekulić Dalibor L., Romčević Nebojša Ž., "Yttrium Orthoferrite Powder Obtained by the Mechanochemical Synthesis" Science of Sintering, 49, no. 3 (2017):277-284,
https://doi.org/10.2298/SOS1703277L .
4
5
5

First-principles calculations of tetragonal FeX (X = S, Se, Te): Magnetism, hyperfine-interaction, and bonding

Koteski, Vasil J.; Ivanovski, Valentin N.; Umićević, Ana; Belošević-Čavor, Jelena; Toprek, Dragan; Mahnke, Heinz-Eberhard

(2017)

TY  - JOUR
AU  - Koteski, Vasil J.
AU  - Ivanovski, Valentin N.
AU  - Umićević, Ana
AU  - Belošević-Čavor, Jelena
AU  - Toprek, Dragan
AU  - Mahnke, Heinz-Eberhard
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1688
AB  - Magnetic ground states, local crystallographic environment of Fe, and hyperfine interaction parameters in tetragonal FeX (X = S, Se, Te) are investigated by means of density functional theory (DFT) calculations using augmented plane waves plus local orbitals (APW + lo) method. We use several different magnetic configurations to evaluate the magnetic and electronic properties of this system, as well as the hyperfine interaction parameters at Fe lattice site. The results obtained for the ground state collinear anti-ferromagnetic arrangement relatively well reproduce the quadrupole splitting and isomer shifts from the available Mossbauer measurements. The Baders atoms in molecule charge density analysis indicates bonding of closed-shell type and a sizable charge transfer from Fe to X. The system properties are sensitive to the structural optimization of the position of the chalcogen atom with respect to the iron plane. (C) 2017 Elsevier B.V. All rights reserved.
T2  - Journal of Magnetism and Magnetic Materials
T1  - First-principles calculations of tetragonal FeX (X = S, Se, Te): Magnetism, hyperfine-interaction, and bonding
VL  - 441
SP  - 769
EP  - 775
DO  - 10.1016/j.jmmm.2017.06.092
ER  - 
@article{
author = "Koteski, Vasil J. and Ivanovski, Valentin N. and Umićević, Ana and Belošević-Čavor, Jelena and Toprek, Dragan and Mahnke, Heinz-Eberhard",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1688",
abstract = "Magnetic ground states, local crystallographic environment of Fe, and hyperfine interaction parameters in tetragonal FeX (X = S, Se, Te) are investigated by means of density functional theory (DFT) calculations using augmented plane waves plus local orbitals (APW + lo) method. We use several different magnetic configurations to evaluate the magnetic and electronic properties of this system, as well as the hyperfine interaction parameters at Fe lattice site. The results obtained for the ground state collinear anti-ferromagnetic arrangement relatively well reproduce the quadrupole splitting and isomer shifts from the available Mossbauer measurements. The Baders atoms in molecule charge density analysis indicates bonding of closed-shell type and a sizable charge transfer from Fe to X. The system properties are sensitive to the structural optimization of the position of the chalcogen atom with respect to the iron plane. (C) 2017 Elsevier B.V. All rights reserved.",
journal = "Journal of Magnetism and Magnetic Materials",
title = "First-principles calculations of tetragonal FeX (X = S, Se, Te): Magnetism, hyperfine-interaction, and bonding",
volume = "441",
pages = "769-775",
doi = "10.1016/j.jmmm.2017.06.092"
}
Koteski, V. J., Ivanovski, V. N., Umićević, A., Belošević-Čavor, J., Toprek, D.,& Mahnke, H. (2017). First-principles calculations of tetragonal FeX (X = S, Se, Te): Magnetism, hyperfine-interaction, and bonding.
Journal of Magnetism and Magnetic Materials, 441, 769-775.
https://doi.org/10.1016/j.jmmm.2017.06.092
Koteski VJ, Ivanovski VN, Umićević A, Belošević-Čavor J, Toprek D, Mahnke H. First-principles calculations of tetragonal FeX (X = S, Se, Te): Magnetism, hyperfine-interaction, and bonding. Journal of Magnetism and Magnetic Materials. 2017;441:769-775
Koteski Vasil J., Ivanovski Valentin N., Umićević Ana, Belošević-Čavor Jelena, Toprek Dragan, Mahnke Heinz-Eberhard, "First-principles calculations of tetragonal FeX (X = S, Se, Te): Magnetism, hyperfine-interaction, and bonding" Journal of Magnetism and Magnetic Materials, 441 (2017):769-775,
https://doi.org/10.1016/j.jmmm.2017.06.092 .
1
1
1

The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder

Jugović, Dragana; Mitrić, Miodrag; Milović, Miloš; Cvjeticanin, Nikola; Jokić, Bojan M.; Umićević, Ana; Uskoković, Dragan

(2017)

TY  - JOUR
AU  - Jugović, Dragana
AU  - Mitrić, Miodrag
AU  - Milović, Miloš
AU  - Cvjeticanin, Nikola
AU  - Jokić, Bojan M.
AU  - Umićević, Ana
AU  - Uskoković, Dragan
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1401
AB  - Low intrinsic electronic conductivity is the main disadvantage of LiFePO4 when used as a cathode material in lithium ion batteries. The paper offers experimental proofs of the theoretical prediction that fluorine doping of LiFePO4 can enhance its electrical conductivity. The LiFePO4 and fluorine-doped LiFePO4 olivine type, carbon free powders are synthesized and examined. The crystal structure refinements in the Pnma space group reveal that doping with fluorine ions preserves the olivine structure, while reducing both the lattice parameters and the antisite defect, and increasing the crystallite size. A small amount of incorporated fluorine enhances the electrical conductivity from 4.6x10(-7) S cm(-1) to 2.3x10(-6) S cm(-1) and has a positive impact on the electrochemical performance. Several spectroscopy techniques (Mossbauer, FTIR, and Raman) reveal differences between the two powders and additionally support the findings of both the Rietveld refinement and the conductivity measurements.
T2  - Ceramics International
T1  - The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder
VL  - 43
IS  - 3
SP  - 3224
EP  - 3230
DO  - 10.1016/j.ceramint.2016.11.149
ER  - 
@article{
author = "Jugović, Dragana and Mitrić, Miodrag and Milović, Miloš and Cvjeticanin, Nikola and Jokić, Bojan M. and Umićević, Ana and Uskoković, Dragan",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1401",
abstract = "Low intrinsic electronic conductivity is the main disadvantage of LiFePO4 when used as a cathode material in lithium ion batteries. The paper offers experimental proofs of the theoretical prediction that fluorine doping of LiFePO4 can enhance its electrical conductivity. The LiFePO4 and fluorine-doped LiFePO4 olivine type, carbon free powders are synthesized and examined. The crystal structure refinements in the Pnma space group reveal that doping with fluorine ions preserves the olivine structure, while reducing both the lattice parameters and the antisite defect, and increasing the crystallite size. A small amount of incorporated fluorine enhances the electrical conductivity from 4.6x10(-7) S cm(-1) to 2.3x10(-6) S cm(-1) and has a positive impact on the electrochemical performance. Several spectroscopy techniques (Mossbauer, FTIR, and Raman) reveal differences between the two powders and additionally support the findings of both the Rietveld refinement and the conductivity measurements.",
journal = "Ceramics International",
title = "The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder",
volume = "43",
number = "3",
pages = "3224-3230",
doi = "10.1016/j.ceramint.2016.11.149"
}
Jugović, D., Mitrić, M., Milović, M., Cvjeticanin, N., Jokić, B. M., Umićević, A.,& Uskoković, D. (2017). The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder.
Ceramics International, 43(3), 3224-3230.
https://doi.org/10.1016/j.ceramint.2016.11.149
Jugović D, Mitrić M, Milović M, Cvjeticanin N, Jokić BM, Umićević A, Uskoković D. The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder. Ceramics International. 2017;43(3):3224-3230
Jugović Dragana, Mitrić Miodrag, Milović Miloš, Cvjeticanin Nikola, Jokić Bojan M., Umićević Ana, Uskoković Dragan, "The influence of fluorine doping on the structural and electrical properties of the LiFePO4 powder" Ceramics International, 43, no. 3 (2017):3224-3230,
https://doi.org/10.1016/j.ceramint.2016.11.149 .
8
10
12

Theoretical investigation of interaction of hydrogen and intermetallic compound YCo5

Radaković, Jana; Batalović, Katarina; Umićević, Ana; Miletic, G. I.

(2017)

TY  - JOUR
AU  - Radaković, Jana
AU  - Batalović, Katarina
AU  - Umićević, Ana
AU  - Miletic, G. I.
PY  - 2017
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/1772
AB  - Stability, magnetic properties, electric field gradients and hyperfine fields of YCo(5)Hx compounds were investigated by using DFT based calculations. Two computational approaches were employed in the study-ultrasoft pseudopotentials with plane waves and all-electron FP(L) APW + lo method. It was found that H atoms prefer off-centered or centered octahedral sites. Enthalpies of formation for alpha - GT beta transition were calculated. Inclusion of zero-point correction reduces agreement between theoretical values of enthalpy of formation obtained from spin-polarized calculations and experimental value. Comparison of theoretical and experimental spin magnetic moments of different YCo5Hx compounds resulted in a reasonable agreement between present theoretical results and previous experimental and theoretical data. Magnetocrystalline anisotropy energy (MAE) was calculated for intermetallic compound YCo5. Reasonable agreement was found between MAE obtained in the present study and the corresponding theoretical and experimental values obtained in earlier studies. (C) 2017 Elsevier B.V. All rights reserved.
T2  - Journal of Alloys and Compounds
T1  - Theoretical investigation of interaction of hydrogen and intermetallic compound YCo5
VL  - 726
SP  - 1085
EP  - 1091
DO  - 10.1016/j.jallcom.2017.08.056
ER  - 
@article{
author = "Radaković, Jana and Batalović, Katarina and Umićević, Ana and Miletic, G. I.",
year = "2017",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/1772",
abstract = "Stability, magnetic properties, electric field gradients and hyperfine fields of YCo(5)Hx compounds were investigated by using DFT based calculations. Two computational approaches were employed in the study-ultrasoft pseudopotentials with plane waves and all-electron FP(L) APW + lo method. It was found that H atoms prefer off-centered or centered octahedral sites. Enthalpies of formation for alpha - GT beta transition were calculated. Inclusion of zero-point correction reduces agreement between theoretical values of enthalpy of formation obtained from spin-polarized calculations and experimental value. Comparison of theoretical and experimental spin magnetic moments of different YCo5Hx compounds resulted in a reasonable agreement between present theoretical results and previous experimental and theoretical data. Magnetocrystalline anisotropy energy (MAE) was calculated for intermetallic compound YCo5. Reasonable agreement was found between MAE obtained in the present study and the corresponding theoretical and experimental values obtained in earlier studies. (C) 2017 Elsevier B.V. All rights reserved.",
journal = "Journal of Alloys and Compounds",
title = "Theoretical investigation of interaction of hydrogen and intermetallic compound YCo5",
volume = "726",
pages = "1085-1091",
doi = "10.1016/j.jallcom.2017.08.056"
}
Radaković, J., Batalović, K., Umićević, A.,& Miletic, G. I. (2017). Theoretical investigation of interaction of hydrogen and intermetallic compound YCo5.
Journal of Alloys and Compounds, 726, 1085-1091.
https://doi.org/10.1016/j.jallcom.2017.08.056
Radaković J, Batalović K, Umićević A, Miletic GI. Theoretical investigation of interaction of hydrogen and intermetallic compound YCo5. Journal of Alloys and Compounds. 2017;726:1085-1091
Radaković Jana, Batalović Katarina, Umićević Ana, Miletic G. I., "Theoretical investigation of interaction of hydrogen and intermetallic compound YCo5" Journal of Alloys and Compounds, 726 (2017):1085-1091,
https://doi.org/10.1016/j.jallcom.2017.08.056 .

Site preference and lattice relaxation around 4d and 5d refractory elements in Ni3Al

Umićević, Ana; Mahnke, Heinz-Eberhard; Belošević-Čavor, Jelena; Cekić, Božidar Đ.; Schumacher, Gerhard; Mađarević, Ivan; Koteski, Vasil J.

(2016)

TY  - JOUR
AU  - Umićević, Ana
AU  - Mahnke, Heinz-Eberhard
AU  - Belošević-Čavor, Jelena
AU  - Cekić, Božidar Đ.
AU  - Schumacher, Gerhard
AU  - Mađarević, Ivan
AU  - Koteski, Vasil J.
PY  - 2016
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/7091
AB  - X-ray absorption spectroscopy is employed to investigate site preference and lattice relaxation around Mo, Ru, Hf, W and Re dopants in Ni3Al. The site occupation preference and the measured distances between the refractory elements as dopants and the nearest host atoms are compared with the results of ab initio calculations within the density functional theory. Combined experimental and theoretical results indicate that Mo, Hf, W and Re atoms reside on the Al sublattice in Ni3Al, while Ru atoms occupy the Ni sublattice. A more pronounced lattice relaxation was detected in the case of Hf and Ru doping, with a strong outward relaxation of the nearest Ni and Al atoms.
T2  - Journal of Synchrotron Radiation
T1  - Site preference and lattice relaxation around 4d and 5d refractory elements in Ni3Al
VL  - 23
SP  - 286
EP  - 292
DO  - 10.1107/S1600577515020688
ER  - 
@article{
author = "Umićević, Ana and Mahnke, Heinz-Eberhard and Belošević-Čavor, Jelena and Cekić, Božidar Đ. and Schumacher, Gerhard and Mađarević, Ivan and Koteski, Vasil J.",
year = "2016",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/7091",
abstract = "X-ray absorption spectroscopy is employed to investigate site preference and lattice relaxation around Mo, Ru, Hf, W and Re dopants in Ni3Al. The site occupation preference and the measured distances between the refractory elements as dopants and the nearest host atoms are compared with the results of ab initio calculations within the density functional theory. Combined experimental and theoretical results indicate that Mo, Hf, W and Re atoms reside on the Al sublattice in Ni3Al, while Ru atoms occupy the Ni sublattice. A more pronounced lattice relaxation was detected in the case of Hf and Ru doping, with a strong outward relaxation of the nearest Ni and Al atoms.",
journal = "Journal of Synchrotron Radiation",
title = "Site preference and lattice relaxation around 4d and 5d refractory elements in Ni3Al",
volume = "23",
pages = "286-292",
doi = "10.1107/S1600577515020688"
}
Umićević, A., Mahnke, H., Belošević-Čavor, J., Cekić, B. Đ., Schumacher, G., Mađarević, I.,& Koteski, V. J. (2016). Site preference and lattice relaxation around 4d and 5d refractory elements in Ni3Al.
Journal of Synchrotron Radiation, 23, 286-292.
https://doi.org/10.1107/S1600577515020688
Umićević A, Mahnke H, Belošević-Čavor J, Cekić BĐ, Schumacher G, Mađarević I, Koteski VJ. Site preference and lattice relaxation around 4d and 5d refractory elements in Ni3Al. Journal of Synchrotron Radiation. 2016;23:286-292
Umićević Ana, Mahnke Heinz-Eberhard, Belošević-Čavor Jelena, Cekić Božidar Đ., Schumacher Gerhard, Mađarević Ivan, Koteski Vasil J., "Site preference and lattice relaxation around 4d and 5d refractory elements in Ni3Al" Journal of Synchrotron Radiation, 23 (2016):286-292,
https://doi.org/10.1107/S1600577515020688 .
1
2
2
2

The influence of fluorine doping on the structural and the electrical properties of LiFePO4 powder

Jugović, Dragana; Mitrić, Miodrag; Milović, Miloš; Cvjetićanin, Nikola; Jokić, Bojan M.; Umićević, Ana; Uskoković, Dragan

(Belgrade : Materials Research Society of Serbia, 2016)

TY  - CONF
AU  - Jugović, Dragana
AU  - Mitrić, Miodrag
AU  - Milović, Miloš
AU  - Cvjetićanin, Nikola
AU  - Jokić, Bojan M.
AU  - Umićević, Ana
AU  - Uskoković, Dragan
PY  - 2016
UR  - http://dais.sanu.ac.rs/123456789/898
UR  - http://www.itn.sanu.ac.rs/opus4/frontdoor/index/index/docId/1180
UR  - http://www.itn.sanu.ac.rs/opus4/files/1180/Jugovic_Yucomat2016-02.pdf
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/7555
AB  - Low intrinsic electronic conductivity is the main weakness of LiFePO4 for the use as cathode material in lithium ion batteries. Here is presented an experimental proof of the theoretical prediction that fluorine doping of LiFePO4 can enhance its electrical conductivity. LiFePO4 and fluorine-doped LiFePO4 olivine type, carbon-free powders are synthesized and examined. Crystal structure refinements in the space group Pnma reveal that doping with fluorine ions preserves olivine structure with the reduction of both the lattice parameters and the antisite defect, and an increase of a crystallite size. A small amount of incorporated fluorine enhances electrical conductivity from 4.6 × 10-7 Scm-1 to 2.3 × 10-6 Scm-1 and has positive impact on the electrochemical performances. Several spectroscopy techniques (Mössbauer, FTIR, and Raman) disclose differences between two powders and additionally support the findings of both the Rietveld refinement and the conductivity measurements.
PB  - Belgrade : Materials Research Society of Serbia
C3  - Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016
T1  - The influence of fluorine doping on the structural and the electrical properties of LiFePO4 powder
SP  - 35
EP  - 35
ER  - 
@conference{
author = "Jugović, Dragana and Mitrić, Miodrag and Milović, Miloš and Cvjetićanin, Nikola and Jokić, Bojan M. and Umićević, Ana and Uskoković, Dragan",
year = "2016",
url = "http://dais.sanu.ac.rs/123456789/898, http://www.itn.sanu.ac.rs/opus4/frontdoor/index/index/docId/1180, http://www.itn.sanu.ac.rs/opus4/files/1180/Jugovic_Yucomat2016-02.pdf, http://vinar.vin.bg.ac.rs/handle/123456789/7555",
abstract = "Low intrinsic electronic conductivity is the main weakness of LiFePO4 for the use as cathode material in lithium ion batteries. Here is presented an experimental proof of the theoretical prediction that fluorine doping of LiFePO4 can enhance its electrical conductivity. LiFePO4 and fluorine-doped LiFePO4 olivine type, carbon-free powders are synthesized and examined. Crystal structure refinements in the space group Pnma reveal that doping with fluorine ions preserves olivine structure with the reduction of both the lattice parameters and the antisite defect, and an increase of a crystallite size. A small amount of incorporated fluorine enhances electrical conductivity from 4.6 × 10-7 Scm-1 to 2.3 × 10-6 Scm-1 and has positive impact on the electrochemical performances. Several spectroscopy techniques (Mössbauer, FTIR, and Raman) disclose differences between two powders and additionally support the findings of both the Rietveld refinement and the conductivity measurements.",
publisher = "Belgrade : Materials Research Society of Serbia",
journal = "Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016",
title = "The influence of fluorine doping on the structural and the electrical properties of LiFePO4 powder",
pages = "35-35"
}
Jugović, D., Mitrić, M., Milović, M., Cvjetićanin, N., Jokić, B. M., Umićević, A.,& Uskoković, D. (2016). The influence of fluorine doping on the structural and the electrical properties of LiFePO4 powder.
Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016
Belgrade : Materials Research Society of Serbia., 35-35.
Jugović D, Mitrić M, Milović M, Cvjetićanin N, Jokić BM, Umićević A, Uskoković D. The influence of fluorine doping on the structural and the electrical properties of LiFePO4 powder. Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016. 2016;:35-35
Jugović Dragana, Mitrić Miodrag, Milović Miloš, Cvjetićanin Nikola, Jokić Bojan M., Umićević Ana, Uskoković Dragan, "The influence of fluorine doping on the structural and the electrical properties of LiFePO4 powder" Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016 (2016):35-35

Site preference of Hf dopant in Ni3Al alloys: A perturbed angular correlation study

Ivanovski, Valentin N.; Cekić, Božidar Đ.; Umićević, Ana; Barudžija, Tanja; Schumacher, G.; Mađarević, Ivan; Koteski, Vasil J.

(2015)

TY  - JOUR
AU  - Ivanovski, Valentin N.
AU  - Cekić, Božidar Đ.
AU  - Umićević, Ana
AU  - Barudžija, Tanja
AU  - Schumacher, G.
AU  - Mađarević, Ivan
AU  - Koteski, Vasil J.
PY  - 2015
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/249
AB  - Perturbed angular correlation measurements of the hyperfine interactions of the Ta-181 probe in the polycrystalline intermetallic Ni3Al doped with 0.5 and 5 at.% Hf were performed in the temperature range 78-1230 K. The observed local hyperfine fields at the Hf-181/Ta-181 probe showed that Hf atoms are substituting on Al sites in the L1(2) structure of Ni3Al. The two minor electric quadrupole interactions that were found for each Ni3Al alloy are discussed taking into account the L1(2) cubic structure and its two tetragonal distortions: D0(22) and L6(0). The presence of two tetragonal transformations of the parent cubic L1(2) lattice in 0.5 at.% Hf and 5 at.% Hf doped Ni3Al was revealed by X-ray diffraction. The ab initio calculations, performed with the projector augmented wave method correctly reproduce the experimental results and enable discussion on the structural and electronic properties of the polycrystalline alloys. The experimental and theoretical investigations showed that hafnium additions prefer aluminum sites in Ni3Al. (C) 2014 Elsevier B.V. All rights reserved.
T2  - Journal of Alloys and Compounds
T1  - Site preference of Hf dopant in Ni3Al alloys: A perturbed angular correlation study
VL  - 622
SP  - 541
EP  - 547
DO  - 10.1016/j.jallcom.2014.10.132
ER  - 
@article{
author = "Ivanovski, Valentin N. and Cekić, Božidar Đ. and Umićević, Ana and Barudžija, Tanja and Schumacher, G. and Mađarević, Ivan and Koteski, Vasil J.",
year = "2015",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/249",
abstract = "Perturbed angular correlation measurements of the hyperfine interactions of the Ta-181 probe in the polycrystalline intermetallic Ni3Al doped with 0.5 and 5 at.% Hf were performed in the temperature range 78-1230 K. The observed local hyperfine fields at the Hf-181/Ta-181 probe showed that Hf atoms are substituting on Al sites in the L1(2) structure of Ni3Al. The two minor electric quadrupole interactions that were found for each Ni3Al alloy are discussed taking into account the L1(2) cubic structure and its two tetragonal distortions: D0(22) and L6(0). The presence of two tetragonal transformations of the parent cubic L1(2) lattice in 0.5 at.% Hf and 5 at.% Hf doped Ni3Al was revealed by X-ray diffraction. The ab initio calculations, performed with the projector augmented wave method correctly reproduce the experimental results and enable discussion on the structural and electronic properties of the polycrystalline alloys. The experimental and theoretical investigations showed that hafnium additions prefer aluminum sites in Ni3Al. (C) 2014 Elsevier B.V. All rights reserved.",
journal = "Journal of Alloys and Compounds",
title = "Site preference of Hf dopant in Ni3Al alloys: A perturbed angular correlation study",
volume = "622",
pages = "541-547",
doi = "10.1016/j.jallcom.2014.10.132"
}
Ivanovski, V. N., Cekić, B. Đ., Umićević, A., Barudžija, T., Schumacher, G., Mađarević, I.,& Koteski, V. J. (2015). Site preference of Hf dopant in Ni3Al alloys: A perturbed angular correlation study.
Journal of Alloys and Compounds, 622, 541-547.
https://doi.org/10.1016/j.jallcom.2014.10.132
Ivanovski VN, Cekić BĐ, Umićević A, Barudžija T, Schumacher G, Mađarević I, Koteski VJ. Site preference of Hf dopant in Ni3Al alloys: A perturbed angular correlation study. Journal of Alloys and Compounds. 2015;622:541-547
Ivanovski Valentin N., Cekić Božidar Đ., Umićević Ana, Barudžija Tanja, Schumacher G., Mađarević Ivan, Koteski Vasil J., "Site preference of Hf dopant in Ni3Al alloys: A perturbed angular correlation study" Journal of Alloys and Compounds, 622 (2015):541-547,
https://doi.org/10.1016/j.jallcom.2014.10.132 .
3
3
3

Evolution of the local structure at Hf sites in SiHfOC upon ceramization of a hafnium-alkoxide-modified polysilsesquioxane: A perturbed angular correlation study

Umićević, Ana; Cekić, Božidar Đ.; Belošević-Čavor, Jelena; Koteski, Vasil J.; Papendorf, Benjamin; Riedel, Ralf; Ionescu, Emanuel

(2015)

TY  - JOUR
AU  - Umićević, Ana
AU  - Cekić, Božidar Đ.
AU  - Belošević-Čavor, Jelena
AU  - Koteski, Vasil J.
AU  - Papendorf, Benjamin
AU  - Riedel, Ralf
AU  - Ionescu, Emanuel
PY  - 2015
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/185
AB  - The evolution of the environment of Hf sites in a hafnium-alkoxide-modified polysilsesquioxane upon polymer-to-ceramic transformation was investigated via the perturbed angular correlation (PAC) method. The results of the PAC measurements on samples thermally treated at temperatures from 400 to 1300 degrees C indicate that Hf is surrounded only by oxygen at all studied temperatures. This finding is in agreement with the evolution pathway of polymer-derived SiHfOC ceramics, which were reported to be generated as single-phase amorphous materials upon pyrolysis of alkoxide-modified polysiloxanes and subsequently to phase separate and crystallize towards HfO2/SiOC nanocomposites. Thus, the results presented here support our previous statement that there is a thermodynamic control on the phase separation and crystallization behavior of Si-M-O-C (M = metal) ceramics (Ionescu et al. 96;2013:1899-1903), which in the case of Hf leads to the precipitation and crystallization of hafnia nanoparticles within a SiOC matrix. (C) 2014 Elsevier Ltd. All rights reserved.
T2  - Journal of the European Ceramic Society
T1  - Evolution of the local structure at Hf sites in SiHfOC upon ceramization of a hafnium-alkoxide-modified polysilsesquioxane: A perturbed angular correlation study
VL  - 35
IS  - 1
SP  - 29
EP  - 35
DO  - 10.1016/j.jeurceramsoc.2014.08.023
ER  - 
@article{
author = "Umićević, Ana and Cekić, Božidar Đ. and Belošević-Čavor, Jelena and Koteski, Vasil J. and Papendorf, Benjamin and Riedel, Ralf and Ionescu, Emanuel",
year = "2015",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/185",
abstract = "The evolution of the environment of Hf sites in a hafnium-alkoxide-modified polysilsesquioxane upon polymer-to-ceramic transformation was investigated via the perturbed angular correlation (PAC) method. The results of the PAC measurements on samples thermally treated at temperatures from 400 to 1300 degrees C indicate that Hf is surrounded only by oxygen at all studied temperatures. This finding is in agreement with the evolution pathway of polymer-derived SiHfOC ceramics, which were reported to be generated as single-phase amorphous materials upon pyrolysis of alkoxide-modified polysiloxanes and subsequently to phase separate and crystallize towards HfO2/SiOC nanocomposites. Thus, the results presented here support our previous statement that there is a thermodynamic control on the phase separation and crystallization behavior of Si-M-O-C (M = metal) ceramics (Ionescu et al. 96;2013:1899-1903), which in the case of Hf leads to the precipitation and crystallization of hafnia nanoparticles within a SiOC matrix. (C) 2014 Elsevier Ltd. All rights reserved.",
journal = "Journal of the European Ceramic Society",
title = "Evolution of the local structure at Hf sites in SiHfOC upon ceramization of a hafnium-alkoxide-modified polysilsesquioxane: A perturbed angular correlation study",
volume = "35",
number = "1",
pages = "29-35",
doi = "10.1016/j.jeurceramsoc.2014.08.023"
}
Umićević, A., Cekić, B. Đ., Belošević-Čavor, J., Koteski, V. J., Papendorf, B., Riedel, R.,& Ionescu, E. (2015). Evolution of the local structure at Hf sites in SiHfOC upon ceramization of a hafnium-alkoxide-modified polysilsesquioxane: A perturbed angular correlation study.
Journal of the European Ceramic Society, 35(1), 29-35.
https://doi.org/10.1016/j.jeurceramsoc.2014.08.023
Umićević A, Cekić BĐ, Belošević-Čavor J, Koteski VJ, Papendorf B, Riedel R, Ionescu E. Evolution of the local structure at Hf sites in SiHfOC upon ceramization of a hafnium-alkoxide-modified polysilsesquioxane: A perturbed angular correlation study. Journal of the European Ceramic Society. 2015;35(1):29-35
Umićević Ana, Cekić Božidar Đ., Belošević-Čavor Jelena, Koteski Vasil J., Papendorf Benjamin, Riedel Ralf, Ionescu Emanuel, "Evolution of the local structure at Hf sites in SiHfOC upon ceramization of a hafnium-alkoxide-modified polysilsesquioxane: A perturbed angular correlation study" Journal of the European Ceramic Society, 35, no. 1 (2015):29-35,
https://doi.org/10.1016/j.jeurceramsoc.2014.08.023 .
11
9
9

Local structure study of Fe dopants in Ni-deficit Ni3Al alloys

Ivanovski, Valentin N.; Umićević, Ana; Belošević-Čavor, Jelena; Lei, Hechang; Li, Lijun; Cekić, Božidar Đ.; Koteski, Vasil J.; Petrovic, C.

(2015)

TY  - JOUR
AU  - Ivanovski, Valentin N.
AU  - Umićević, Ana
AU  - Belošević-Čavor, Jelena
AU  - Lei, Hechang
AU  - Li, Lijun
AU  - Cekić, Božidar Đ.
AU  - Koteski, Vasil J.
AU  - Petrovic, C.
PY  - 2015
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/749
AB  - The local electronic and magnetic structure, hyperfine interactions, and phase composition of polycrystalline Ni-deficient Ni3-xFexAl (x = 0.18 and 0.36) were investigated by means of Fe-57 Mossbauer spectroscopy. The samples were characterized by X-ray diffraction and magnetization measurements. The ab initio calculations performed with the projector augmented wave method and the calculations of the energies of iron point defects were done to elucidate the electronic structure and site preference of Fe doped Ni3Al. The value of calculated electric field gradient tensor V-zz = 1.6 10(21) Vm(-2) matches well with the results of Mossbauer spectroscopy and indicates that the Fe atoms occupy Ni sites. (C) 2015 Elsevier B.V. All rights reserved.
T2  - Journal of Alloys and Compounds
T1  - Local structure study of Fe dopants in Ni-deficit Ni3Al alloys
VL  - 651
SP  - 705
EP  - 711
DO  - 10.1016/j.jallcom.2015.08.171
ER  - 
@article{
author = "Ivanovski, Valentin N. and Umićević, Ana and Belošević-Čavor, Jelena and Lei, Hechang and Li, Lijun and Cekić, Božidar Đ. and Koteski, Vasil J. and Petrovic, C.",
year = "2015",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/749",
abstract = "The local electronic and magnetic structure, hyperfine interactions, and phase composition of polycrystalline Ni-deficient Ni3-xFexAl (x = 0.18 and 0.36) were investigated by means of Fe-57 Mossbauer spectroscopy. The samples were characterized by X-ray diffraction and magnetization measurements. The ab initio calculations performed with the projector augmented wave method and the calculations of the energies of iron point defects were done to elucidate the electronic structure and site preference of Fe doped Ni3Al. The value of calculated electric field gradient tensor V-zz = 1.6 10(21) Vm(-2) matches well with the results of Mossbauer spectroscopy and indicates that the Fe atoms occupy Ni sites. (C) 2015 Elsevier B.V. All rights reserved.",
journal = "Journal of Alloys and Compounds",
title = "Local structure study of Fe dopants in Ni-deficit Ni3Al alloys",
volume = "651",
pages = "705-711",
doi = "10.1016/j.jallcom.2015.08.171"
}
Ivanovski, V. N., Umićević, A., Belošević-Čavor, J., Lei, H., Li, L., Cekić, B. Đ., Koteski, V. J.,& Petrovic, C. (2015). Local structure study of Fe dopants in Ni-deficit Ni3Al alloys.
Journal of Alloys and Compounds, 651, 705-711.
https://doi.org/10.1016/j.jallcom.2015.08.171
Ivanovski VN, Umićević A, Belošević-Čavor J, Lei H, Li L, Cekić BĐ, Koteski VJ, Petrovic C. Local structure study of Fe dopants in Ni-deficit Ni3Al alloys. Journal of Alloys and Compounds. 2015;651:705-711
Ivanovski Valentin N., Umićević Ana, Belošević-Čavor Jelena, Lei Hechang, Li Lijun, Cekić Božidar Đ., Koteski Vasil J., Petrovic C., "Local structure study of Fe dopants in Ni-deficit Ni3Al alloys" Journal of Alloys and Compounds, 651 (2015):705-711,
https://doi.org/10.1016/j.jallcom.2015.08.171 .
3
4
4

Hydrogen diffusion in MgH2 doped with Ti, Mn and Fe

Koteski, Vasil J.; Belošević-Čavor, Jelena; Batalović, Katarina; Radaković, Jana; Umićević, Ana

(2015)

TY  - JOUR
AU  - Koteski, Vasil J.
AU  - Belošević-Čavor, Jelena
AU  - Batalović, Katarina
AU  - Radaković, Jana
AU  - Umićević, Ana
PY  - 2015
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/254
AB  - Incorporation of suitable dopants in MgH2 is widely investigated as the way of improving hydrogen storage characteristics of this material. The catalytic role of transition metal dopants on hydrogen desorption from MgH2 is very promising, but further attention is required in order to optimize the experimental methods and design materials with desired properties. In this paper we investigate the role of Ti, Fe, and Mn on the transport properties of hydrogen in MgH2, which are marked as limiting factor in the effort to lower the hydrogen desorption temperature. Taking into account the lattice relaxation around the impurities, we consider a number of different diffusion paths in the pure and doped system. Using PAW DFT calculations in combination with the NEB method, we demonstrate that the diffusion of the most relevant positively charged hydrogen vacancy and negatively charged interstitial hydrogen atom is locally hindered by the presence of the impurity atoms.
T2  - RSC Advances
T1  - Hydrogen diffusion in MgH2 doped with Ti, Mn and Fe
VL  - 5
IS  - 44
SP  - 34894
EP  - 34899
DO  - 10.1039/c5ra04168f
ER  - 
@article{
author = "Koteski, Vasil J. and Belošević-Čavor, Jelena and Batalović, Katarina and Radaković, Jana and Umićević, Ana",
year = "2015",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/254",
abstract = "Incorporation of suitable dopants in MgH2 is widely investigated as the way of improving hydrogen storage characteristics of this material. The catalytic role of transition metal dopants on hydrogen desorption from MgH2 is very promising, but further attention is required in order to optimize the experimental methods and design materials with desired properties. In this paper we investigate the role of Ti, Fe, and Mn on the transport properties of hydrogen in MgH2, which are marked as limiting factor in the effort to lower the hydrogen desorption temperature. Taking into account the lattice relaxation around the impurities, we consider a number of different diffusion paths in the pure and doped system. Using PAW DFT calculations in combination with the NEB method, we demonstrate that the diffusion of the most relevant positively charged hydrogen vacancy and negatively charged interstitial hydrogen atom is locally hindered by the presence of the impurity atoms.",
journal = "RSC Advances",
title = "Hydrogen diffusion in MgH2 doped with Ti, Mn and Fe",
volume = "5",
number = "44",
pages = "34894-34899",
doi = "10.1039/c5ra04168f"
}
Koteski, V. J., Belošević-Čavor, J., Batalović, K., Radaković, J.,& Umićević, A. (2015). Hydrogen diffusion in MgH2 doped with Ti, Mn and Fe.
RSC Advances, 5(44), 34894-34899.
https://doi.org/10.1039/c5ra04168f
Koteski VJ, Belošević-Čavor J, Batalović K, Radaković J, Umićević A. Hydrogen diffusion in MgH2 doped with Ti, Mn and Fe. RSC Advances. 2015;5(44):34894-34899
Koteski Vasil J., Belošević-Čavor Jelena, Batalović Katarina, Radaković Jana, Umićević Ana, "Hydrogen diffusion in MgH2 doped with Ti, Mn and Fe" RSC Advances, 5, no. 44 (2015):34894-34899,
https://doi.org/10.1039/c5ra04168f .
15
15
16

Hf dopants in gamma -Ni3Al alloy

Ivanovski, Valentin N.; Cekić, Božidar Đ.; Umićević, Ana; Belošević-Čavor, Jelena; Schumacher, G.; Koteski, Vasil J.; Barudžija, Tanja

(2013)

TY  - JOUR
AU  - Ivanovski, Valentin N.
AU  - Cekić, Božidar Đ.
AU  - Umićević, Ana
AU  - Belošević-Čavor, Jelena
AU  - Schumacher, G.
AU  - Koteski, Vasil J.
AU  - Barudžija, Tanja
PY  - 2013
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/5625
AB  - The Time Differential Perturbed Angular (TDPAC) measurements of nuclear quadrupole interactions (NQIs) at Ta-181 ion probe in the polycrystalline intermetallic alloy gamma-Ni3Al doped with 0.2 at. % Hf were performed in the temperature range 78-1230K, in order to determine the lattice location of Hf atoms in the ordered gamma-Ni3Al structure. The two NQIs obtained are discussed within the present L1(2) cubic structure and a tetragonal distortion of L1(2) to another two DO22 and L6(0) type structures. The first low frequency NQI at the site of the Ta-181 ion-probe after substitution of aluminum for hafnium in DO22 at ambient temperature, is v(Q1)(300 K) = 39(1) MHz with eta(1) = 0. The corresponding high frequency value on the second crystallographic site in L6(0), is v(Q2)(300 K) = 204(14) MHz with eta(2) = 0.47(11). These two NQIs have different temperature behavior. The presence of both DO22 and L6(0) tetragonal distortions of the parent cubic L1(2) lattice, detected after adding 0.2 at. % Hf, are with modulations to the lattice constant (a) with a ratio (c/a), 2.04 and 0.87, respectively. Ab initio calculations of electronic and structural properties and hyperfine parameters at the Ta-181 ion probe of the gamma-Ni3Al-0.2 at. % Hf alloy were performed using the full potential augmented plane wave plus local-orbital (APW+lo) method as implemented in the WIEN2k code. The accuracy of the calculations and comparison with the experimental results enabled us to identify the observed hyperfine interactions and to infer the EFG sign that cannot be measured in conventional TDPAC measurements. (C) 2013 AIP Publishing LLC.
T2  - Journal of Applied Physics
T1  - Hf dopants in gamma -Ni3Al alloy
VL  - 114
IS  - 6
DO  - 10.1063/1.4818317
ER  - 
@article{
author = "Ivanovski, Valentin N. and Cekić, Božidar Đ. and Umićević, Ana and Belošević-Čavor, Jelena and Schumacher, G. and Koteski, Vasil J. and Barudžija, Tanja",
year = "2013",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/5625",
abstract = "The Time Differential Perturbed Angular (TDPAC) measurements of nuclear quadrupole interactions (NQIs) at Ta-181 ion probe in the polycrystalline intermetallic alloy gamma-Ni3Al doped with 0.2 at. % Hf were performed in the temperature range 78-1230K, in order to determine the lattice location of Hf atoms in the ordered gamma-Ni3Al structure. The two NQIs obtained are discussed within the present L1(2) cubic structure and a tetragonal distortion of L1(2) to another two DO22 and L6(0) type structures. The first low frequency NQI at the site of the Ta-181 ion-probe after substitution of aluminum for hafnium in DO22 at ambient temperature, is v(Q1)(300 K) = 39(1) MHz with eta(1) = 0. The corresponding high frequency value on the second crystallographic site in L6(0), is v(Q2)(300 K) = 204(14) MHz with eta(2) = 0.47(11). These two NQIs have different temperature behavior. The presence of both DO22 and L6(0) tetragonal distortions of the parent cubic L1(2) lattice, detected after adding 0.2 at. % Hf, are with modulations to the lattice constant (a) with a ratio (c/a), 2.04 and 0.87, respectively. Ab initio calculations of electronic and structural properties and hyperfine parameters at the Ta-181 ion probe of the gamma-Ni3Al-0.2 at. % Hf alloy were performed using the full potential augmented plane wave plus local-orbital (APW+lo) method as implemented in the WIEN2k code. The accuracy of the calculations and comparison with the experimental results enabled us to identify the observed hyperfine interactions and to infer the EFG sign that cannot be measured in conventional TDPAC measurements. (C) 2013 AIP Publishing LLC.",
journal = "Journal of Applied Physics",
title = "Hf dopants in gamma -Ni3Al alloy",
volume = "114",
number = "6",
doi = "10.1063/1.4818317"
}
Ivanovski, V. N., Cekić, B. Đ., Umićević, A., Belošević-Čavor, J., Schumacher, G., Koteski, V. J.,& Barudžija, T. (2013). Hf dopants in gamma -Ni3Al alloy.
Journal of Applied Physics, 114(6).
https://doi.org/10.1063/1.4818317
Ivanovski VN, Cekić BĐ, Umićević A, Belošević-Čavor J, Schumacher G, Koteski VJ, Barudžija T. Hf dopants in gamma -Ni3Al alloy. Journal of Applied Physics. 2013;114(6)
Ivanovski Valentin N., Cekić Božidar Đ., Umićević Ana, Belošević-Čavor Jelena, Schumacher G., Koteski Vasil J., Barudžija Tanja, "Hf dopants in gamma -Ni3Al alloy" Journal of Applied Physics, 114, no. 6 (2013),
https://doi.org/10.1063/1.4818317 .
3
3
3

Perturbed Angular Correlation Investigation of the Electric Field Gradient At Ta-181 Probe in the Hf2ni7 Compound

Cekić, Božidar Đ.; Umićević, Ana; Ivanovski, Valentin N.; Hu, Rongwei; Petrovic, Cedomir; David, Bohumil; Barudžija, Tanja

(2012)

TY  - JOUR
AU  - Cekić, Božidar Đ.
AU  - Umićević, Ana
AU  - Ivanovski, Valentin N.
AU  - Hu, Rongwei
AU  - Petrovic, Cedomir
AU  - David, Bohumil
AU  - Barudžija, Tanja
PY  - 2012
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/4925
AB  - The perturbed angular correlation method was employed to study the temperature dependence of electric field gradients at the Ta-181 probe in the polycrystalline Hf2Ni7 compound. The temperature evolution of the sample content was measured using high-temperature X-ray diffraction. To check the magnetic order of the sample, magnetization measurements and additional perturbed angular correlation measurements with externally applied magnetic field were performed. All obtained spectra showed no evidence of magnetic order of the Hf2Ni7 phase. Within the experimental resolution of the apparatus, the measured electric field gradients at Ta-181 probe for the two inequivalent Hf-181/Ta-181 sites in the Hf2Ni7 compound appeared as one in the range of 78-944 K. A single quadrupole interaction implies that the electric field gradients at the two Hf sites must be quite similar. At 293 K, the measured quadrupole interaction parameters are v(Q) = 433(1) MHz and eta = 0.300(4). An increase of the quadrupole frequency and a gradual rising of the asymmetry parameter were observed with increasing temperature. The high-temperature X-ray diffraction indicated a build up of HfO2 above 693 K.
T2  - Nuclear technology and radiation protection
T1  - Perturbed Angular Correlation Investigation of the Electric Field Gradient At Ta-181 Probe in the Hf2ni7 Compound
VL  - 27
IS  - 2
SP  - 95
EP  - 102
DO  - 10.2298/NTRP1202095C
ER  - 
@article{
author = "Cekić, Božidar Đ. and Umićević, Ana and Ivanovski, Valentin N. and Hu, Rongwei and Petrovic, Cedomir and David, Bohumil and Barudžija, Tanja",
year = "2012",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/4925",
abstract = "The perturbed angular correlation method was employed to study the temperature dependence of electric field gradients at the Ta-181 probe in the polycrystalline Hf2Ni7 compound. The temperature evolution of the sample content was measured using high-temperature X-ray diffraction. To check the magnetic order of the sample, magnetization measurements and additional perturbed angular correlation measurements with externally applied magnetic field were performed. All obtained spectra showed no evidence of magnetic order of the Hf2Ni7 phase. Within the experimental resolution of the apparatus, the measured electric field gradients at Ta-181 probe for the two inequivalent Hf-181/Ta-181 sites in the Hf2Ni7 compound appeared as one in the range of 78-944 K. A single quadrupole interaction implies that the electric field gradients at the two Hf sites must be quite similar. At 293 K, the measured quadrupole interaction parameters are v(Q) = 433(1) MHz and eta = 0.300(4). An increase of the quadrupole frequency and a gradual rising of the asymmetry parameter were observed with increasing temperature. The high-temperature X-ray diffraction indicated a build up of HfO2 above 693 K.",
journal = "Nuclear technology and radiation protection",
title = "Perturbed Angular Correlation Investigation of the Electric Field Gradient At Ta-181 Probe in the Hf2ni7 Compound",
volume = "27",
number = "2",
pages = "95-102",
doi = "10.2298/NTRP1202095C"
}
Cekić, B. Đ., Umićević, A., Ivanovski, V. N., Hu, R., Petrovic, C., David, B.,& Barudžija, T. (2012). Perturbed Angular Correlation Investigation of the Electric Field Gradient At Ta-181 Probe in the Hf2ni7 Compound.
Nuclear technology and radiation protection, 27(2), 95-102.
https://doi.org/10.2298/NTRP1202095C
Cekić BĐ, Umićević A, Ivanovski VN, Hu R, Petrovic C, David B, Barudžija T. Perturbed Angular Correlation Investigation of the Electric Field Gradient At Ta-181 Probe in the Hf2ni7 Compound. Nuclear technology and radiation protection. 2012;27(2):95-102
Cekić Božidar Đ., Umićević Ana, Ivanovski Valentin N., Hu Rongwei, Petrovic Cedomir, David Bohumil, Barudžija Tanja, "Perturbed Angular Correlation Investigation of the Electric Field Gradient At Ta-181 Probe in the Hf2ni7 Compound" Nuclear technology and radiation protection, 27, no. 2 (2012):95-102,
https://doi.org/10.2298/NTRP1202095C .

Mineral Characterization of Soil Type Ranker Formed on Serpentines Occurring in Southern Belgrade Environs Bubanj Potok

Cekić, Božidar Đ.; Ivanovski, Valentin N.; Đorđević, Aleksandar N.; Aleksić, Velimir; Tomić, Zorica; Bogdanovic, Stefan; Umićević, Ana

(2012)

TY  - JOUR
AU  - Cekić, Božidar Đ.
AU  - Ivanovski, Valentin N.
AU  - Đorđević, Aleksandar N.
AU  - Aleksić, Velimir
AU  - Tomić, Zorica
AU  - Bogdanovic, Stefan
AU  - Umićević, Ana
PY  - 2012
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/4927
AB  - The paper addresses the issue of health risk associated with the presence of chrysotile in the soil type ranker formed on massive serpentines occurring in the area of Bubanj Potok, a settlement located in the southern Belgrade environs, Serbia. Characterization of the ranker soil was conducted by scanning electron microscopy, X-ray diffraction, micro-Raman spectroscopy and transmission Fe-57 Mossbauer spectroscopy. Scanning electron microscopy figures showed regular shaped smectite (montmorillonite) particles, aggregates of chlorite, and elongated sheets of serpentines minerals antigorite. X-ray diffraction analysis confirmed the presence of detrital mineral quartz polymorph as well as minor amounts of other mineral species. Micro-Raman spectroscopy identified the presence of dominant minerals, such as montmorillonite, kaolinite, muscovite, gypsum, calcite, albite, amphiboles (hornblende/kaersutite) and orthoclase. Important polymorph silica modifications of quartz, olivine (forsterite), pyroxene (enstatite/ferrosilite, diopside/hedenbergite), and serpentine (antigorite/lizardite/chrysotile) were identified.
T2  - Nuclear technology and radiation protection
T1  - Mineral Characterization of Soil Type Ranker Formed on Serpentines Occurring in Southern Belgrade Environs Bubanj Potok
VL  - 27
IS  - 2
SP  - 131
EP  - 136
DO  - 10.2298/NTRP1202131C
ER  - 
@article{
author = "Cekić, Božidar Đ. and Ivanovski, Valentin N. and Đorđević, Aleksandar N. and Aleksić, Velimir and Tomić, Zorica and Bogdanovic, Stefan and Umićević, Ana",
year = "2012",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/4927",
abstract = "The paper addresses the issue of health risk associated with the presence of chrysotile in the soil type ranker formed on massive serpentines occurring in the area of Bubanj Potok, a settlement located in the southern Belgrade environs, Serbia. Characterization of the ranker soil was conducted by scanning electron microscopy, X-ray diffraction, micro-Raman spectroscopy and transmission Fe-57 Mossbauer spectroscopy. Scanning electron microscopy figures showed regular shaped smectite (montmorillonite) particles, aggregates of chlorite, and elongated sheets of serpentines minerals antigorite. X-ray diffraction analysis confirmed the presence of detrital mineral quartz polymorph as well as minor amounts of other mineral species. Micro-Raman spectroscopy identified the presence of dominant minerals, such as montmorillonite, kaolinite, muscovite, gypsum, calcite, albite, amphiboles (hornblende/kaersutite) and orthoclase. Important polymorph silica modifications of quartz, olivine (forsterite), pyroxene (enstatite/ferrosilite, diopside/hedenbergite), and serpentine (antigorite/lizardite/chrysotile) were identified.",
journal = "Nuclear technology and radiation protection",
title = "Mineral Characterization of Soil Type Ranker Formed on Serpentines Occurring in Southern Belgrade Environs Bubanj Potok",
volume = "27",
number = "2",
pages = "131-136",
doi = "10.2298/NTRP1202131C"
}
Cekić, B. Đ., Ivanovski, V. N., Đorđević, A. N., Aleksić, V., Tomić, Z., Bogdanovic, S.,& Umićević, A. (2012). Mineral Characterization of Soil Type Ranker Formed on Serpentines Occurring in Southern Belgrade Environs Bubanj Potok.
Nuclear technology and radiation protection, 27(2), 131-136.
https://doi.org/10.2298/NTRP1202131C
Cekić BĐ, Ivanovski VN, Đorđević AN, Aleksić V, Tomić Z, Bogdanovic S, Umićević A. Mineral Characterization of Soil Type Ranker Formed on Serpentines Occurring in Southern Belgrade Environs Bubanj Potok. Nuclear technology and radiation protection. 2012;27(2):131-136
Cekić Božidar Đ., Ivanovski Valentin N., Đorđević Aleksandar N., Aleksić Velimir, Tomić Zorica, Bogdanovic Stefan, Umićević Ana, "Mineral Characterization of Soil Type Ranker Formed on Serpentines Occurring in Southern Belgrade Environs Bubanj Potok" Nuclear technology and radiation protection, 27, no. 2 (2012):131-136,
https://doi.org/10.2298/NTRP1202131C .

Mossbauer spectroscopic analysis of Nd2Fe14B/alpha-Fe hard magnetic nanocomposites

Cekić, Božidar Đ.; Ivanovski, Valentin N.; Codescu, Mirela; Umićević, Ana; Barudžija, Tanja; Patroi, Eros

(2011)

TY  - CONF
AU  - Cekić, Božidar Đ.
AU  - Ivanovski, Valentin N.
AU  - Codescu, Mirela
AU  - Umićević, Ana
AU  - Barudžija, Tanja
AU  - Patroi, Eros
PY  - 2011
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/6914
AB  - Among novel magnetic intermetallics based on rare earth-transition compounds, the Nd2Fe14B/alpha-Fe isotropic nanocomposites have been obtained by recrystallization from an amorphous phase, prepared by melt spinning. For variable 5 wt.% Fe and 10 wt.% Fe contents we recorded transmission Fe-57 Mossbauer spectra at the room temperature, hardened of the alpha-Fe phase by exchange interactions. The spectra have been analyzed in terms of ten Zeeman sextets and one paramagnetic doublet related to the Nd1.1Fe4B4 phase. One sextet corresponds to the alpha-Fe phase, whereas others are attributed to six non-equivalent Fe sites in the Nd2Fe14B structure, namely 16k(1), 16k(2), 8j(1), 8j(2), 4c, and 4e. The three remaining sextets belong to the Fe3B structure with three inequivalent Fe sites Fe-I(8g), Fe-II(8g) and Fe-III(8g). All relevant parameters for both nanocomposites: the magnetic hyperfine field, the isomer shift and the quadrupole splitting are determined for each of these sites.
C3  - Solid State Phenomena
T1  - Mossbauer spectroscopic analysis of Nd2Fe14B/alpha-Fe hard magnetic nanocomposites
VL  - 170
SP  - 154
EP  - 159
DO  - 10.4028/www.scientific.net/SSP.170.154
ER  - 
@conference{
author = "Cekić, Božidar Đ. and Ivanovski, Valentin N. and Codescu, Mirela and Umićević, Ana and Barudžija, Tanja and Patroi, Eros",
year = "2011",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/6914",
abstract = "Among novel magnetic intermetallics based on rare earth-transition compounds, the Nd2Fe14B/alpha-Fe isotropic nanocomposites have been obtained by recrystallization from an amorphous phase, prepared by melt spinning. For variable 5 wt.% Fe and 10 wt.% Fe contents we recorded transmission Fe-57 Mossbauer spectra at the room temperature, hardened of the alpha-Fe phase by exchange interactions. The spectra have been analyzed in terms of ten Zeeman sextets and one paramagnetic doublet related to the Nd1.1Fe4B4 phase. One sextet corresponds to the alpha-Fe phase, whereas others are attributed to six non-equivalent Fe sites in the Nd2Fe14B structure, namely 16k(1), 16k(2), 8j(1), 8j(2), 4c, and 4e. The three remaining sextets belong to the Fe3B structure with three inequivalent Fe sites Fe-I(8g), Fe-II(8g) and Fe-III(8g). All relevant parameters for both nanocomposites: the magnetic hyperfine field, the isomer shift and the quadrupole splitting are determined for each of these sites.",
journal = "Solid State Phenomena",
title = "Mossbauer spectroscopic analysis of Nd2Fe14B/alpha-Fe hard magnetic nanocomposites",
volume = "170",
pages = "154-159",
doi = "10.4028/www.scientific.net/SSP.170.154"
}
Cekić, B. Đ., Ivanovski, V. N., Codescu, M., Umićević, A., Barudžija, T.,& Patroi, E. (2011). Mossbauer spectroscopic analysis of Nd2Fe14B/alpha-Fe hard magnetic nanocomposites.
Solid State Phenomena, 170, 154-159.
https://doi.org/10.4028/www.scientific.net/SSP.170.154
Cekić BĐ, Ivanovski VN, Codescu M, Umićević A, Barudžija T, Patroi E. Mossbauer spectroscopic analysis of Nd2Fe14B/alpha-Fe hard magnetic nanocomposites. Solid State Phenomena. 2011;170:154-159
Cekić Božidar Đ., Ivanovski Valentin N., Codescu Mirela, Umićević Ana, Barudžija Tanja, Patroi Eros, "Mossbauer spectroscopic analysis of Nd2Fe14B/alpha-Fe hard magnetic nanocomposites" Solid State Phenomena, 170 (2011):154-159,
https://doi.org/10.4028/www.scientific.net/SSP.170.154 .
1

Mossbauer Study of Hffe2 and Hf0.75ta0.25fe2

Cekić, Božidar Đ.; Ivanovski, Valentin N.; Zak, T.; Stojić, Dragica Lj.; Belošević-Čavor, Jelena; Koteski, Vasil J.; Umićević, Ana

(2011)

TY  - JOUR
AU  - Cekić, Božidar Đ.
AU  - Ivanovski, Valentin N.
AU  - Zak, T.
AU  - Stojić, Dragica Lj.
AU  - Belošević-Čavor, Jelena
AU  - Koteski, Vasil J.
AU  - Umićević, Ana
PY  - 2011
UR  - http://vinar.vin.bg.ac.rs/handle/123456789/4410
AB  - Mossbauer spectrum measured on ferromagnetic HfFe2 at 296 K, consists of four six-line components and one doublet. The Laves phase HfFe2 has three kinds of crystal structures: cubic MgCu2(C15), hexagonal MgZn2(C14) and MgNi2(C36). We assigned two sextets to the 2a and 6h sites of C14, one to the C15 and the fourth sextet to the minor presence of alpha-Fe. The doublet originates from small amount of FeO, apparently a corrosion product. The pseudobinary compound of Hf0.75Ta0.25Fe2 (C14) undergoes the first - order transition to antiferromagnetic (AFM) state at about 180 K due to the strong spin fluctuation. Therefore, a magnetic sextet and a doublet were observed for the spectra assigned to the 6h and 2a site. The second sextet is attached to the minor presence of Fe3O4.
T2  - Romanian Journal of Physics
T1  - Mossbauer Study of Hffe2 and Hf0.75ta0.25fe2
VL  - 56
IS  - 5-6
SP  - 719
EP  - 723
ER  - 
@article{
author = "Cekić, Božidar Đ. and Ivanovski, Valentin N. and Zak, T. and Stojić, Dragica Lj. and Belošević-Čavor, Jelena and Koteski, Vasil J. and Umićević, Ana",
year = "2011",
url = "http://vinar.vin.bg.ac.rs/handle/123456789/4410",
abstract = "Mossbauer spectrum measured on ferromagnetic HfFe2 at 296 K, consists of four six-line components and one doublet. The Laves phase HfFe2 has three kinds of crystal structures: cubic MgCu2(C15), hexagonal MgZn2(C14) and MgNi2(C36). We assigned two sextets to the 2a and 6h sites of C14, one to the C15 and the fourth sextet to the minor presence of alpha-Fe. The doublet originates from small amount of FeO, apparently a corrosion product. The pseudobinary compound of Hf0.75Ta0.25Fe2 (C14) undergoes the first - order transition to antiferromagnetic (AFM) state at about 180 K due to the strong spin fluctuation. Therefore, a magnetic sextet and a doublet were observed for the spectra assigned to the 6h and 2a site. The second sextet is attached to the minor presence of Fe3O4.",
journal = "Romanian Journal of Physics",
title = "Mossbauer Study of Hffe2 and Hf0.75ta0.25fe2",
volume = "56",
number = "5-6",
pages = "719-723"
}
Cekić, B. Đ., Ivanovski, V. N., Zak, T., Stojić, D. Lj., Belošević-Čavor, J., Koteski, V. J.,& Umićević, A. (2011). Mossbauer Study of Hffe2 and Hf0.75ta0.25fe2.
Romanian Journal of Physics, 56(5-6), 719-723.
Cekić BĐ, Ivanovski VN, Zak T, Stojić DL, Belošević-Čavor J, Koteski VJ, Umićević A. Mossbauer Study of Hffe2 and Hf0.75ta0.25fe2. Romanian Journal of Physics. 2011;56(5-6):719-723
Cekić Božidar Đ., Ivanovski Valentin N., Zak T., Stojić Dragica Lj., Belošević-Čavor Jelena, Koteski Vasil J., Umićević Ana, "Mossbauer Study of Hffe2 and Hf0.75ta0.25fe2" Romanian Journal of Physics, 56, no. 5-6 (2011):719-723
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