TY  - JOUR
AU  - Barudžija, Tanja
AU  - Perović, Marija M.
AU  - Bošković, Marko
AU  - Cvjetićanin, Nikola
AU  - Gyergyek, Sašo
AU  - Mitrić, Miodrag
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8743
AB  - Memory effect due to spin-glass state below about 20 K has been illustrated in the hollandite-type α-KxMnO2 monocrystalline nanorods by systematic magnetization measurements including temperature- and time-dependent magnetization curves in low fields. In this work, we succeeded in writing, reading, and deleting 8-bits digital information in the investigated system. These results show that α-KxMnO2 is a good candidate material for a thermal memory cell. The phenomenological droplet model was used in the description of the observed memory effect, whose origin in α-KxMnO2 is associated with bulk properties, doping and frustration. © 2019 Elsevier B.V.
T2  - Journal of Alloys and Compounds
T1  - Magnetic memory effect in hollandite-type α-K MnO2 monocrystalline nanorods
VL  - 820
SP  - 153406
DO  - 10.1016/j.jallcom.2019.153406
ER  - 

@article{
author = "Barudžija, Tanja and Perović, Marija M. and Bošković, Marko and Cvjetićanin, Nikola and Gyergyek, Sašo and Mitrić, Miodrag",
year = "2020",
abstract = "Memory effect due to spin-glass state below about 20 K has been illustrated in the hollandite-type α-KxMnO2 monocrystalline nanorods by systematic magnetization measurements including temperature- and time-dependent magnetization curves in low fields. In this work, we succeeded in writing, reading, and deleting 8-bits digital information in the investigated system. These results show that α-KxMnO2 is a good candidate material for a thermal memory cell. The phenomenological droplet model was used in the description of the observed memory effect, whose origin in α-KxMnO2 is associated with bulk properties, doping and frustration. © 2019 Elsevier B.V.",
journal = "Journal of Alloys and Compounds",
title = "Magnetic memory effect in hollandite-type α-K MnO2 monocrystalline nanorods",
volume = "820",
pages = "153406",
doi = "10.1016/j.jallcom.2019.153406"
}

Barudžija, T., Perović, M. M., Bošković, M., Cvjetićanin, N., Gyergyek, S.,& Mitrić, M.. (2020). Magnetic memory effect in hollandite-type α-K MnO2 monocrystalline nanorods. in Journal of Alloys and Compounds, 820, 153406.
https://doi.org/10.1016/j.jallcom.2019.153406

Barudžija T, Perović MM, Bošković M, Cvjetićanin N, Gyergyek S, Mitrić M. Magnetic memory effect in hollandite-type α-K MnO2 monocrystalline nanorods. in Journal of Alloys and Compounds. 2020;820:153406.
doi:10.1016/j.jallcom.2019.153406 .

Barudžija, Tanja, Perović, Marija M., Bošković, Marko, Cvjetićanin, Nikola, Gyergyek, Sašo, Mitrić, Miodrag, "Magnetic memory effect in hollandite-type α-K MnO2 monocrystalline nanorods" in Journal of Alloys and Compounds, 820 (2020):153406,
https://doi.org/10.1016/j.jallcom.2019.153406 . .

TY  - JOUR
AU  - Kusigerski, Vladan
AU  - Illés, Erzsébet
AU  - Blanuša, Jovan
AU  - Gyergyek, Sašo
AU  - Bošković, Marko
AU  - Perović, Marija M.
AU  - Spasojević, Vojislav
PY  - 2019
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/7983
AB  - Ferrofluids based on magnesium substituted magnetite nanoparticles MgxFe3−xO4 (x = 0.1; 0.2; 0.4) were synthesised by a chemical co-precipitation method. Their physical properties have been compared with those of the magnetite based ferrofluid obtained by the same synthesis route. Both XRD and TEM studies showed particle size decrease with the increased Mg content while DLS experiments pointed to the more prominent aggregation of Mg-containing nanoparticles. Magnetic properties investigation conducted on the powder (i.e. dried) specimens showed decrease of magnetization values with increased Mg content except for the lowest concentration of x = 0.1 where substantial saturation magnetization rise of about 40% was recorded at room temperature. Heating abilities of the studied ferrofluids under the applied AC fields (SAR values) also showed decreasing trend with the increased Mg content even for x = 0.1 sample despite its elevated magnetization value. This trend has been understood as a consequence of the changed intrinsic nanoparticle properties such as size and magnetic anisotropy, as well as contribution of a collective behaviour due to an increased nanoparticle aggregation in Mg-doped systems.
T2  - Journal of Magnetism and Magnetic Materials
T1  - Magnetic properties and heating efficacy of magnesium doped magnetite nanoparticles obtained by co-precipitation method
VL  - 475
SP  - 470
EP  - 478
DO  - 10.1016/j.jmmm.2018.11.127
ER  - 

@article{
author = "Kusigerski, Vladan and Illés, Erzsébet and Blanuša, Jovan and Gyergyek, Sašo and Bošković, Marko and Perović, Marija M. and Spasojević, Vojislav",
year = "2019",
abstract = "Ferrofluids based on magnesium substituted magnetite nanoparticles MgxFe3−xO4 (x = 0.1; 0.2; 0.4) were synthesised by a chemical co-precipitation method. Their physical properties have been compared with those of the magnetite based ferrofluid obtained by the same synthesis route. Both XRD and TEM studies showed particle size decrease with the increased Mg content while DLS experiments pointed to the more prominent aggregation of Mg-containing nanoparticles. Magnetic properties investigation conducted on the powder (i.e. dried) specimens showed decrease of magnetization values with increased Mg content except for the lowest concentration of x = 0.1 where substantial saturation magnetization rise of about 40% was recorded at room temperature. Heating abilities of the studied ferrofluids under the applied AC fields (SAR values) also showed decreasing trend with the increased Mg content even for x = 0.1 sample despite its elevated magnetization value. This trend has been understood as a consequence of the changed intrinsic nanoparticle properties such as size and magnetic anisotropy, as well as contribution of a collective behaviour due to an increased nanoparticle aggregation in Mg-doped systems.",
journal = "Journal of Magnetism and Magnetic Materials",
title = "Magnetic properties and heating efficacy of magnesium doped magnetite nanoparticles obtained by co-precipitation method",
volume = "475",
pages = "470-478",
doi = "10.1016/j.jmmm.2018.11.127"
}

Kusigerski, V., Illés, E., Blanuša, J., Gyergyek, S., Bošković, M., Perović, M. M.,& Spasojević, V.. (2019). Magnetic properties and heating efficacy of magnesium doped magnetite nanoparticles obtained by co-precipitation method. in Journal of Magnetism and Magnetic Materials, 475, 470-478.
https://doi.org/10.1016/j.jmmm.2018.11.127

Kusigerski V, Illés E, Blanuša J, Gyergyek S, Bošković M, Perović MM, Spasojević V. Magnetic properties and heating efficacy of magnesium doped magnetite nanoparticles obtained by co-precipitation method. in Journal of Magnetism and Magnetic Materials. 2019;475:470-478.
doi:10.1016/j.jmmm.2018.11.127 .

Kusigerski, Vladan, Illés, Erzsébet, Blanuša, Jovan, Gyergyek, Sašo, Bošković, Marko, Perović, Marija M., Spasojević, Vojislav, "Magnetic properties and heating efficacy of magnesium doped magnetite nanoparticles obtained by co-precipitation method" in Journal of Magnetism and Magnetic Materials, 475 (2019):470-478,
https://doi.org/10.1016/j.jmmm.2018.11.127 . .

TY  - JOUR
AU  - Ivetić, Tamara B.
AU  - Tadić, Marin
AU  - Jagodič, Marko
AU  - Gyergyek, Sašo
AU  - Štrbac, Goran R.
AU  - Lukić-Petrović, Svetlana R.
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1316
AB  - This paper reports on novel cobalt oxide nanoparticles (NPs) embedded in an amorphous silica (SiO2) matrix, synthesized using a modified sol-gel method. SEM and TEM images show as-synthesized particles to aggregate in the shape of spheres and less than 5 nm in size, while XRD and SAED analysis both point to well crystallized cubic spinel cobalt oxide phase with an average crystallite size of about 4.6 nm. Raman analysis confirms the formation of cobalt (III) oxide (Co3O4) NPs. As-synthesized Co3O4 single-nanocrystallite has magnetic properties that correlate with finite size effects and uncompensated surface spins. Temperature dependence of ZFC-FC magnetization curves reveals a sharp peak around 10 K which corresponds to the blocking temperature. A Curie-Weiss behavior of magnetization above 25 K shows lower Neel temperature of the sample compared with its bulk counterpart T-N=40 K (possibly due to crystal defects and nano-dimensionality of the particles). The magnetic measurements exhibit high magnetization at low temperatures (M-s=54.3 emu/g) which can be associated with random canting of the particles surface spins and uncompensated spins in the core which tends to interact ferromagnetically at low temperatures. The initial magnetization curve falls out from the hysteresis loop at 5 K, which could be also the effect of surface spins. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
T2  - Ceramics International
T1  - Structure and magnetic properties of Co3O4/SiO2 nanocomposite synthesized using combustion assisted sol-gel method
VL  - 42
IS  - 16
SP  - 18312
EP  - 18317
DO  - 10.1016/j.ceramint.2016.08.159
ER  - 

@article{
author = "Ivetić, Tamara B. and Tadić, Marin and Jagodič, Marko and Gyergyek, Sašo and Štrbac, Goran R. and Lukić-Petrović, Svetlana R.",
year = "2016",
abstract = "This paper reports on novel cobalt oxide nanoparticles (NPs) embedded in an amorphous silica (SiO2) matrix, synthesized using a modified sol-gel method. SEM and TEM images show as-synthesized particles to aggregate in the shape of spheres and less than 5 nm in size, while XRD and SAED analysis both point to well crystallized cubic spinel cobalt oxide phase with an average crystallite size of about 4.6 nm. Raman analysis confirms the formation of cobalt (III) oxide (Co3O4) NPs. As-synthesized Co3O4 single-nanocrystallite has magnetic properties that correlate with finite size effects and uncompensated surface spins. Temperature dependence of ZFC-FC magnetization curves reveals a sharp peak around 10 K which corresponds to the blocking temperature. A Curie-Weiss behavior of magnetization above 25 K shows lower Neel temperature of the sample compared with its bulk counterpart T-N=40 K (possibly due to crystal defects and nano-dimensionality of the particles). The magnetic measurements exhibit high magnetization at low temperatures (M-s=54.3 emu/g) which can be associated with random canting of the particles surface spins and uncompensated spins in the core which tends to interact ferromagnetically at low temperatures. The initial magnetization curve falls out from the hysteresis loop at 5 K, which could be also the effect of surface spins. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.",
journal = "Ceramics International",
title = "Structure and magnetic properties of Co3O4/SiO2 nanocomposite synthesized using combustion assisted sol-gel method",
volume = "42",
number = "16",
pages = "18312-18317",
doi = "10.1016/j.ceramint.2016.08.159"
}

Ivetić, T. B., Tadić, M., Jagodič, M., Gyergyek, S., Štrbac, G. R.,& Lukić-Petrović, S. R.. (2016). Structure and magnetic properties of Co3O4/SiO2 nanocomposite synthesized using combustion assisted sol-gel method. in Ceramics International, 42(16), 18312-18317.
https://doi.org/10.1016/j.ceramint.2016.08.159

Ivetić TB, Tadić M, Jagodič M, Gyergyek S, Štrbac GR, Lukić-Petrović SR. Structure and magnetic properties of Co3O4/SiO2 nanocomposite synthesized using combustion assisted sol-gel method. in Ceramics International. 2016;42(16):18312-18317.
doi:10.1016/j.ceramint.2016.08.159 .

Ivetić, Tamara B., Tadić, Marin, Jagodič, Marko, Gyergyek, Sašo, Štrbac, Goran R., Lukić-Petrović, Svetlana R., "Structure and magnetic properties of Co3O4/SiO2 nanocomposite synthesized using combustion assisted sol-gel method" in Ceramics International, 42, no. 16 (2016):18312-18317,
https://doi.org/10.1016/j.ceramint.2016.08.159 . .

TY  - JOUR
AU  - Kopanja, Lazar
AU  - Žunić, Dragiša
AU  - Lončar, Boris B.
AU  - Gyergyek, Sašo
AU  - Tadić, Marin
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1198
AB  - We propose using a new circularity measure, and an ellipticity measure. Observing an example of hematite (alpha-Fe2O3) nanoparticles, we compared and discussed a new circularity measure, with a standard measure. It has been shown that using the new measure gives better results when working with low-quality images or with low-resolution images. Using the same images modified ellipticity measure has also been discussed. We have analyzed the problems arising from computing the elongation of a shape. We have shown that the standard approach to compute elongation is not appropriate for some particles. We presented the application of the modified approach to solve this problem. (C) 2016 Elsevier Ltd. All rights reserved.
T2  - Measurement
T1  - Quantifying shapes of nanoparticles using modified circularity and ellipticity measures
VL  - 92
SP  - 252
EP  - 263
DO  - 10.1016/j.measurement.2016.06.021
ER  - 

@article{
author = "Kopanja, Lazar and Žunić, Dragiša and Lončar, Boris B. and Gyergyek, Sašo and Tadić, Marin",
year = "2016",
abstract = "We propose using a new circularity measure, and an ellipticity measure. Observing an example of hematite (alpha-Fe2O3) nanoparticles, we compared and discussed a new circularity measure, with a standard measure. It has been shown that using the new measure gives better results when working with low-quality images or with low-resolution images. Using the same images modified ellipticity measure has also been discussed. We have analyzed the problems arising from computing the elongation of a shape. We have shown that the standard approach to compute elongation is not appropriate for some particles. We presented the application of the modified approach to solve this problem. (C) 2016 Elsevier Ltd. All rights reserved.",
journal = "Measurement",
title = "Quantifying shapes of nanoparticles using modified circularity and ellipticity measures",
volume = "92",
pages = "252-263",
doi = "10.1016/j.measurement.2016.06.021"
}

Kopanja, L., Žunić, D., Lončar, B. B., Gyergyek, S.,& Tadić, M.. (2016). Quantifying shapes of nanoparticles using modified circularity and ellipticity measures. in Measurement, 92, 252-263.
https://doi.org/10.1016/j.measurement.2016.06.021

Kopanja L, Žunić D, Lončar BB, Gyergyek S, Tadić M. Quantifying shapes of nanoparticles using modified circularity and ellipticity measures. in Measurement. 2016;92:252-263.
doi:10.1016/j.measurement.2016.06.021 .

Kopanja, Lazar, Žunić, Dragiša, Lončar, Boris B., Gyergyek, Sašo, Tadić, Marin, "Quantifying shapes of nanoparticles using modified circularity and ellipticity measures" in Measurement, 92 (2016):252-263,
https://doi.org/10.1016/j.measurement.2016.06.021 . .