TY  - JOUR
AU  - Abozaid, Rouaida Mohamed
AU  - Stojanović, Dušica
AU  - Radisavljević, Anđela
AU  - Sević, Dragutin M.
AU  - Rabasović, Maja S.
AU  - Radović, I. M.
AU  - Radojević, Vesna
PY  - 2020
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4573
AB  - Processing and characterization of polymer nanocomposites based on poly(methyl methacrylate) (PMMA) matrix with embedded core-shell CdSe/ZnS quantum dots were investigated. Nanocomposites were obtained via solution casting and electrospinning. FESEM analysis revealed that the processing with electrospinning enables better dispersion of quantum dots. Time-resolved laser induced fluorescence measurements confirmed uniform size of QDs in fibers with the emission at only one wavelength. Oxidation effects in quantum dots were removed with the use of PMMA as a host, and the core remained active, which was confirmed with FTIR analysis and time-resolved laser induced fluorescence measurements.
PB  - Natl Inst Optoelectronics, Bucharest-Magurele
T2  - Journal of Optoelectronics and Advanced Materials
T1  - Polymer composite films and nanofibers doped with core-shell quantum dots
EP  - 74
IS  - 1-2
SP  - 67
VL  - 22
UR  - https://hdl.handle.net/21.15107/rcub_vinar_9034
ER  - 

@article{
author = "Abozaid, Rouaida Mohamed and Stojanović, Dušica and Radisavljević, Anđela and Sević, Dragutin M. and Rabasović, Maja S. and Radović, I. M. and Radojević, Vesna",
year = "2020",
abstract = "Processing and characterization of polymer nanocomposites based on poly(methyl methacrylate) (PMMA) matrix with embedded core-shell CdSe/ZnS quantum dots were investigated. Nanocomposites were obtained via solution casting and electrospinning. FESEM analysis revealed that the processing with electrospinning enables better dispersion of quantum dots. Time-resolved laser induced fluorescence measurements confirmed uniform size of QDs in fibers with the emission at only one wavelength. Oxidation effects in quantum dots were removed with the use of PMMA as a host, and the core remained active, which was confirmed with FTIR analysis and time-resolved laser induced fluorescence measurements.",
publisher = "Natl Inst Optoelectronics, Bucharest-Magurele",
journal = "Journal of Optoelectronics and Advanced Materials",
title = "Polymer composite films and nanofibers doped with core-shell quantum dots",
pages = "74-67",
number = "1-2",
volume = "22",
url = "https://hdl.handle.net/21.15107/rcub_vinar_9034"
}

Abozaid, R. M., Stojanović, D., Radisavljević, A., Sević, D. M., Rabasović, M. S., Radović, I. M.,& Radojević, V.. (2020). Polymer composite films and nanofibers doped with core-shell quantum dots. in Journal of Optoelectronics and Advanced Materials
Natl Inst Optoelectronics, Bucharest-Magurele., 22(1-2), 67-74.
https://hdl.handle.net/21.15107/rcub_vinar_9034

Abozaid RM, Stojanović D, Radisavljević A, Sević DM, Rabasović MS, Radović IM, Radojević V. Polymer composite films and nanofibers doped with core-shell quantum dots. in Journal of Optoelectronics and Advanced Materials. 2020;22(1-2):67-74.
https://hdl.handle.net/21.15107/rcub_vinar_9034 .

Abozaid, Rouaida Mohamed, Stojanović, Dušica, Radisavljević, Anđela, Sević, Dragutin M., Rabasović, Maja S., Radović, I. M., Radojević, Vesna, "Polymer composite films and nanofibers doped with core-shell quantum dots" in Journal of Optoelectronics and Advanced Materials, 22, no. 1-2 (2020):67-74,
https://hdl.handle.net/21.15107/rcub_vinar_9034 .

TY  - JOUR
AU  - Abozaid, Rouaida Mohamed
AU  - Lazarević, Zorica Ž.
AU  - Radović, Ivana
AU  - Gilić, Martina
AU  - Sević, Dragutin M.
AU  - Rabasović, Maja S.
AU  - Radojević, Vesna
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4225
AB  - Processing and characterization of polymer nanocomposites based on poly (methyl methacrylate) (PMMA) matrix with embedded core-shell CdSe/ZnS quantum dots (QD's) were presented in this work. The aim is to preserve the optical activity of QD's in nanocomposite processing with improved mechanical properties. The modification of QD's CdSe/ZnS-PMMA interface was achieved with 3-mercaptopropyltrimethoxysilane (MPTMS). Nanocomposites were processed by solution casting. The samples of pure PMMA, and composites with unmodified and silane modified QD's CdSe/ZnS were processed. FTIR analysis revealed modification of QD's with silane and characteristic bonding with PMMA matrix. Raman spectrum confirms a presence of alloyed layer at the core-shell interface. Time-resolved laser induced fluorescence measurements confirmed slight blue shift in QD's CdSe/ZnS-PMMA composite without interface modification, while there was a slight red shift with modified particles. Oxidation effects in quantum dots were removed with the use of PMMA as a host, and the core remained active, which was confirmed with FTIR analysis and time-resolved laser induced fluorescence measurements.
PB  - Elsevier Science Bv, Amsterdam
T2  - Optical Materials
T1  - Optical properties and fluorescence of quantum dots CdSe/ZnS-PMMA composite films with interface modifications
EP  - 410
SP  - 405
VL  - 92
DO  - 10.1016/j.optmat.2019.05.012
ER  - 

@article{
author = "Abozaid, Rouaida Mohamed and Lazarević, Zorica Ž. and Radović, Ivana and Gilić, Martina and Sević, Dragutin M. and Rabasović, Maja S. and Radojević, Vesna",
year = "2019",
abstract = "Processing and characterization of polymer nanocomposites based on poly (methyl methacrylate) (PMMA) matrix with embedded core-shell CdSe/ZnS quantum dots (QD's) were presented in this work. The aim is to preserve the optical activity of QD's in nanocomposite processing with improved mechanical properties. The modification of QD's CdSe/ZnS-PMMA interface was achieved with 3-mercaptopropyltrimethoxysilane (MPTMS). Nanocomposites were processed by solution casting. The samples of pure PMMA, and composites with unmodified and silane modified QD's CdSe/ZnS were processed. FTIR analysis revealed modification of QD's with silane and characteristic bonding with PMMA matrix. Raman spectrum confirms a presence of alloyed layer at the core-shell interface. Time-resolved laser induced fluorescence measurements confirmed slight blue shift in QD's CdSe/ZnS-PMMA composite without interface modification, while there was a slight red shift with modified particles. Oxidation effects in quantum dots were removed with the use of PMMA as a host, and the core remained active, which was confirmed with FTIR analysis and time-resolved laser induced fluorescence measurements.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Optical Materials",
title = "Optical properties and fluorescence of quantum dots CdSe/ZnS-PMMA composite films with interface modifications",
pages = "410-405",
volume = "92",
doi = "10.1016/j.optmat.2019.05.012"
}

Abozaid, R. M., Lazarević, Z. Ž., Radović, I., Gilić, M., Sević, D. M., Rabasović, M. S.,& Radojević, V.. (2019). Optical properties and fluorescence of quantum dots CdSe/ZnS-PMMA composite films with interface modifications. in Optical Materials
Elsevier Science Bv, Amsterdam., 92, 405-410.
https://doi.org/10.1016/j.optmat.2019.05.012

Abozaid RM, Lazarević ZŽ, Radović I, Gilić M, Sević DM, Rabasović MS, Radojević V. Optical properties and fluorescence of quantum dots CdSe/ZnS-PMMA composite films with interface modifications. in Optical Materials. 2019;92:405-410.
doi:10.1016/j.optmat.2019.05.012 .

Abozaid, Rouaida Mohamed, Lazarević, Zorica Ž., Radović, Ivana, Gilić, Martina, Sević, Dragutin M., Rabasović, Maja S., Radojević, Vesna, "Optical properties and fluorescence of quantum dots CdSe/ZnS-PMMA composite films with interface modifications" in Optical Materials, 92 (2019):405-410,
https://doi.org/10.1016/j.optmat.2019.05.012 . .

TY  - JOUR
AU  - Abozaid, Rouaida Mohamed
AU  - Lazarević, Zorica Z.
AU  - Tomić, Nataša
AU  - Milutinović, Aleksandra
AU  - Sević, Dragutin M.
AU  - Rabasović, Maja S.
AU  - Radojević, Vesna
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4145
AB  - In this article, we report characterization of the layered composite fabricated from Nd3+ doped calcium twigstate single crystal (CaWO4 :Nd3+) and poly(methyl methacrylate) - PMMA with various organic-inorganic interfaces: CaWO4:Nd3+/MPTMS, CaWO4:Nd3+/PMMA and CaWO4:Nd3+/MPTMS/PMMA, a novel approach to optical composite materials. A trivalent neodymium-doped CaWO4 single crystal was grown by the Czochralski method. Poly(methyl methacrylate) - PMMA, was used as a protective polymer coating and (3-mercaptopropyl) trimethoxy silane (MPTMS), with aim to provide better adhesion between the crystal surface and the polymer in the composite. The optical properties of the crystal plates with various layers applied on surface were characterized using FTIR absorption, IR reflectivity, Raman and photoluminescence spectroscopy. Performed tests on the structural, optical and photo-luminescent properties of composites can facilitate the research of potential applications in micro- and optoelectronics. Hardness of CaWO4:Nd3+ before and after surface modification was determined by micro Vickers hardness test. The improved hardness of composite with the use of the MPTMS as an adhesion primer before PMMA was achieved. FTIR spectroscopy indicates the establishing of chemical bonding between single crystal layer, silane and polymer layer. Raman and PL spectroscopy confirm that optical properties of crystal with polymer layers were preserved.
PB  - Elsevier, Amsterdam
T2  - Optical Materials
T1  - Optical properties CaWO4:Nd3+/PMMA composite layered structures
VL  - 96
DO  - 10.1016/j.optmat.2019.109361
ER  - 

@article{
author = "Abozaid, Rouaida Mohamed and Lazarević, Zorica Z. and Tomić, Nataša and Milutinović, Aleksandra and Sević, Dragutin M. and Rabasović, Maja S. and Radojević, Vesna",
year = "2019",
abstract = "In this article, we report characterization of the layered composite fabricated from Nd3+ doped calcium twigstate single crystal (CaWO4 :Nd3+) and poly(methyl methacrylate) - PMMA with various organic-inorganic interfaces: CaWO4:Nd3+/MPTMS, CaWO4:Nd3+/PMMA and CaWO4:Nd3+/MPTMS/PMMA, a novel approach to optical composite materials. A trivalent neodymium-doped CaWO4 single crystal was grown by the Czochralski method. Poly(methyl methacrylate) - PMMA, was used as a protective polymer coating and (3-mercaptopropyl) trimethoxy silane (MPTMS), with aim to provide better adhesion between the crystal surface and the polymer in the composite. The optical properties of the crystal plates with various layers applied on surface were characterized using FTIR absorption, IR reflectivity, Raman and photoluminescence spectroscopy. Performed tests on the structural, optical and photo-luminescent properties of composites can facilitate the research of potential applications in micro- and optoelectronics. Hardness of CaWO4:Nd3+ before and after surface modification was determined by micro Vickers hardness test. The improved hardness of composite with the use of the MPTMS as an adhesion primer before PMMA was achieved. FTIR spectroscopy indicates the establishing of chemical bonding between single crystal layer, silane and polymer layer. Raman and PL spectroscopy confirm that optical properties of crystal with polymer layers were preserved.",
publisher = "Elsevier, Amsterdam",
journal = "Optical Materials",
title = "Optical properties CaWO4:Nd3+/PMMA composite layered structures",
volume = "96",
doi = "10.1016/j.optmat.2019.109361"
}

Abozaid, R. M., Lazarević, Z. Z., Tomić, N., Milutinović, A., Sević, D. M., Rabasović, M. S.,& Radojević, V.. (2019). Optical properties CaWO4:Nd3+/PMMA composite layered structures. in Optical Materials
Elsevier, Amsterdam., 96.
https://doi.org/10.1016/j.optmat.2019.109361

Abozaid RM, Lazarević ZZ, Tomić N, Milutinović A, Sević DM, Rabasović MS, Radojević V. Optical properties CaWO4:Nd3+/PMMA composite layered structures. in Optical Materials. 2019;96.
doi:10.1016/j.optmat.2019.109361 .

Abozaid, Rouaida Mohamed, Lazarević, Zorica Z., Tomić, Nataša, Milutinović, Aleksandra, Sević, Dragutin M., Rabasović, Maja S., Radojević, Vesna, "Optical properties CaWO4:Nd3+/PMMA composite layered structures" in Optical Materials, 96 (2019),
https://doi.org/10.1016/j.optmat.2019.109361 . .

TY  - JOUR
AU  - Abozaid, Rouaida Mohamed
AU  - Lazarević, Zorica Z.
AU  - Radojević, Vesna
AU  - Rabasović, Maja S.
AU  - Sević, Dragutin M.
AU  - Rabasović, Mihailo D.
AU  - Romčević, Nebojša Ž.
PY  - 2018
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3910
AB  - The aim of the current work was to assess obtain a single crystal of calcium tungstate doped with neodymium - (CaWO4:Nd3+), and after that, the crystal was characterized with various spectroscopic methods. The single crystal was grown from the melt using the Czochralski method in air. By optimizing growth conditions,  lt 001 gt -oriented CaWO4:Nd3+ crystalc up to 10 mm in diameter were grown. Number of dislocations in obtained crystal was 10(2) per cm(2). Micro hardness was measured with the Vickers pyramid. Anisotropy in  lt 001 gt  direction was not observed. Selected CaWO4:Nd3+ single crystal was cut into several tiles with the diamond saw. The plates were polished with a diamond paste. The crystal structure is confirmed by X-ray diffraction. The obtained crystal was studied by Raman and infrared spectroscopy. Seven Raman and six IR optical active modes predicted by group theory are observed. FTIR confirmed the occurrence of all the functional groups and bonds in this material. From the FTIR spectrum, a strong peak of 862 cm(-1) has been obtained due to the stretching vibration of WO42- in scheelite structure, and a weak but sharp band at 433 cm(-1) has been noticed due to the metal-oxygen (Ca-O) band. Estimated luminescence lifetime of F-4(5/2) - the I-4(9/2) transition is about 120 mu s; estimated luminescence lifetime of F-4(3/2) - the I-4(9/2) transition is about 140 mu s. All performed investigations show that the obtained CaWO4:Nd3+ single crystal has good optical quality, which was the goal of this work.
PB  - Međunarodni Institut za nauku o sinterovanju, Beograd
T2  - Science of Sintering
T1  - Characterization of Neodymium Doped Calcium Tungstate Single Crystal by Raman, IR and Luminescence Spectroscopy
EP  - 455
IS  - 4
SP  - 445
VL  - 50
DO  - 10.2298/SOS1804445A
ER  - 

@article{
author = "Abozaid, Rouaida Mohamed and Lazarević, Zorica Z. and Radojević, Vesna and Rabasović, Maja S. and Sević, Dragutin M. and Rabasović, Mihailo D. and Romčević, Nebojša Ž.",
year = "2018",
abstract = "The aim of the current work was to assess obtain a single crystal of calcium tungstate doped with neodymium - (CaWO4:Nd3+), and after that, the crystal was characterized with various spectroscopic methods. The single crystal was grown from the melt using the Czochralski method in air. By optimizing growth conditions,  lt 001 gt -oriented CaWO4:Nd3+ crystalc up to 10 mm in diameter were grown. Number of dislocations in obtained crystal was 10(2) per cm(2). Micro hardness was measured with the Vickers pyramid. Anisotropy in  lt 001 gt  direction was not observed. Selected CaWO4:Nd3+ single crystal was cut into several tiles with the diamond saw. The plates were polished with a diamond paste. The crystal structure is confirmed by X-ray diffraction. The obtained crystal was studied by Raman and infrared spectroscopy. Seven Raman and six IR optical active modes predicted by group theory are observed. FTIR confirmed the occurrence of all the functional groups and bonds in this material. From the FTIR spectrum, a strong peak of 862 cm(-1) has been obtained due to the stretching vibration of WO42- in scheelite structure, and a weak but sharp band at 433 cm(-1) has been noticed due to the metal-oxygen (Ca-O) band. Estimated luminescence lifetime of F-4(5/2) - the I-4(9/2) transition is about 120 mu s; estimated luminescence lifetime of F-4(3/2) - the I-4(9/2) transition is about 140 mu s. All performed investigations show that the obtained CaWO4:Nd3+ single crystal has good optical quality, which was the goal of this work.",
publisher = "Međunarodni Institut za nauku o sinterovanju, Beograd",
journal = "Science of Sintering",
title = "Characterization of Neodymium Doped Calcium Tungstate Single Crystal by Raman, IR and Luminescence Spectroscopy",
pages = "455-445",
number = "4",
volume = "50",
doi = "10.2298/SOS1804445A"
}

Abozaid, R. M., Lazarević, Z. Z., Radojević, V., Rabasović, M. S., Sević, D. M., Rabasović, M. D.,& Romčević, N. Ž.. (2018). Characterization of Neodymium Doped Calcium Tungstate Single Crystal by Raman, IR and Luminescence Spectroscopy. in Science of Sintering
Međunarodni Institut za nauku o sinterovanju, Beograd., 50(4), 445-455.
https://doi.org/10.2298/SOS1804445A

Abozaid RM, Lazarević ZZ, Radojević V, Rabasović MS, Sević DM, Rabasović MD, Romčević NŽ. Characterization of Neodymium Doped Calcium Tungstate Single Crystal by Raman, IR and Luminescence Spectroscopy. in Science of Sintering. 2018;50(4):445-455.
doi:10.2298/SOS1804445A .

Abozaid, Rouaida Mohamed, Lazarević, Zorica Z., Radojević, Vesna, Rabasović, Maja S., Sević, Dragutin M., Rabasović, Mihailo D., Romčević, Nebojša Ž., "Characterization of Neodymium Doped Calcium Tungstate Single Crystal by Raman, IR and Luminescence Spectroscopy" in Science of Sintering, 50, no. 4 (2018):445-455,
https://doi.org/10.2298/SOS1804445A . .