TY  - JOUR
AU  - Nenadović, Miloš
AU  - Ivanović, Marija
AU  - Kisić, Danilo
AU  - Bundaleski, Nenad
AU  - Pavlović, Vera
AU  - Knežević, Sanja
AU  - Kljajević, Ljiljana
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12727
AB  - In the present paper, polymerization of alkali activated metakaolin (MK) and its structural changing, using 2M NaOH, 8M NaOH, and 16M NaOH solutions were followed by means of X-ray photoelectron spectroscopy (XPS), Diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), Raman spectroscopy and Scanning electron microscopy (SEM). XPS analysis revealed that changing of NaOH concentration did not affect the types of formed bonds in the material. At the same time, the amount of sodium and aluminum increased with the NaOH molarity. The latter steps could be especially interesting because it may indicate the possibility of 'dosing' the amount of Al incorporated by changing the NaOH concentration in the solution. DRIFT analysis revealed that the absorption band for AlIV located at 800 cm-1 is shifted towards the smaller values. Changing the concentration of NaOH, the chemical content did not change, but the structural changes are observed. Raman spectroscopy detected that the most dominant peaks at ∼400 cm-1 and 519 cm-1 originate from Si-O-Al and Si-O-Si bending modes. With increasing the NaOH concentration, peaks at 1019-1060 cm-1 become more prominent as a result of polymerization. Both analyzes (DRIFT and Raman) confirmed the presence of quartz. SEM analysis showed that different structures are created by changing the concentration of NaOH.
AB  - У овом раду, праћена је полимеризација алкално активираног метакаолина (МК) и његове структурне промене, коришћењем 2М NaOH, 8М NaOH и 16М раствора NaOH. Промене су праћене рендгенском фотоелектронском спектроскопијом (XPS), дифузном рефлексијом инфрацрвене Фуријеове трансформације (DRIFT), Рамановом спектроскопијом и скенирајућом електронском микроскопијом (SEM). XPS анализа је показала да промена концентрације NaOH није утицала на типове формираних веза у материјалу. Истовремено, количина натријума и алуминијума се повећавала са моларношћу NaOH. Последњи кораци могу бити посебно интересантни јер могу указивати на могућност 'дозирања' количине Al инкорпорираног променом концентрације NaOH у раствору. DRIFT анализа је открила да је опсег апсорпције за AlIV који се налази на 800 cm-1 померен ка мањим вредностима. Променом концентрације NaOH, хемијски садржај се није мењао, али су уочене структурне промене. Раманова спектроскопија је открила да најдоминантнији пикови на 400 cm-1 и 519 cm-1 потичу из Si-О-Al и Si-О-Si начина савијања хемијских веза. Са повећањем концентрације NaOH, пикови на 1019-1060 cm-1 постају све израженији као резултат полимеризације. Обе анализе (DRIFT и Раман) потврдиле су присуство кварца. SEM анализа је показала да се променом концентрације NaOH стварају различите структуре.
T2  - Science of Sintering
T1  - Changes in the physicochemical properties of geopolymer gels as a function of NaOH concentration
VL  - 55
IS  - 4
SP  - 509
EP  - 519
DO  - 10.2298/SOS220624020N
ER  - 

@article{
author = "Nenadović, Miloš and Ivanović, Marija and Kisić, Danilo and Bundaleski, Nenad and Pavlović, Vera and Knežević, Sanja and Kljajević, Ljiljana",
year = "2024",
abstract = "In the present paper, polymerization of alkali activated metakaolin (MK) and its structural changing, using 2M NaOH, 8M NaOH, and 16M NaOH solutions were followed by means of X-ray photoelectron spectroscopy (XPS), Diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), Raman spectroscopy and Scanning electron microscopy (SEM). XPS analysis revealed that changing of NaOH concentration did not affect the types of formed bonds in the material. At the same time, the amount of sodium and aluminum increased with the NaOH molarity. The latter steps could be especially interesting because it may indicate the possibility of 'dosing' the amount of Al incorporated by changing the NaOH concentration in the solution. DRIFT analysis revealed that the absorption band for AlIV located at 800 cm-1 is shifted towards the smaller values. Changing the concentration of NaOH, the chemical content did not change, but the structural changes are observed. Raman spectroscopy detected that the most dominant peaks at ∼400 cm-1 and 519 cm-1 originate from Si-O-Al and Si-O-Si bending modes. With increasing the NaOH concentration, peaks at 1019-1060 cm-1 become more prominent as a result of polymerization. Both analyzes (DRIFT and Raman) confirmed the presence of quartz. SEM analysis showed that different structures are created by changing the concentration of NaOH., У овом раду, праћена је полимеризација алкално активираног метакаолина (МК) и његове структурне промене, коришћењем 2М NaOH, 8М NaOH и 16М раствора NaOH. Промене су праћене рендгенском фотоелектронском спектроскопијом (XPS), дифузном рефлексијом инфрацрвене Фуријеове трансформације (DRIFT), Рамановом спектроскопијом и скенирајућом електронском микроскопијом (SEM). XPS анализа је показала да промена концентрације NaOH није утицала на типове формираних веза у материјалу. Истовремено, количина натријума и алуминијума се повећавала са моларношћу NaOH. Последњи кораци могу бити посебно интересантни јер могу указивати на могућност 'дозирања' количине Al инкорпорираног променом концентрације NaOH у раствору. DRIFT анализа је открила да је опсег апсорпције за AlIV који се налази на 800 cm-1 померен ка мањим вредностима. Променом концентрације NaOH, хемијски садржај се није мењао, али су уочене структурне промене. Раманова спектроскопија је открила да најдоминантнији пикови на 400 cm-1 и 519 cm-1 потичу из Si-О-Al и Si-О-Si начина савијања хемијских веза. Са повећањем концентрације NaOH, пикови на 1019-1060 cm-1 постају све израженији као резултат полимеризације. Обе анализе (DRIFT и Раман) потврдиле су присуство кварца. SEM анализа је показала да се променом концентрације NaOH стварају различите структуре.",
journal = "Science of Sintering",
title = "Changes in the physicochemical properties of geopolymer gels as a function of NaOH concentration",
volume = "55",
number = "4",
pages = "509-519",
doi = "10.2298/SOS220624020N"
}

Nenadović, M., Ivanović, M., Kisić, D., Bundaleski, N., Pavlović, V., Knežević, S.,& Kljajević, L.. (2024). Changes in the physicochemical properties of geopolymer gels as a function of NaOH concentration. in Science of Sintering, 55(4), 509-519.
https://doi.org/10.2298/SOS220624020N

Nenadović M, Ivanović M, Kisić D, Bundaleski N, Pavlović V, Knežević S, Kljajević L. Changes in the physicochemical properties of geopolymer gels as a function of NaOH concentration. in Science of Sintering. 2024;55(4):509-519.
doi:10.2298/SOS220624020N .

Nenadović, Miloš, Ivanović, Marija, Kisić, Danilo, Bundaleski, Nenad, Pavlović, Vera, Knežević, Sanja, Kljajević, Ljiljana, "Changes in the physicochemical properties of geopolymer gels as a function of NaOH concentration" in Science of Sintering, 55, no. 4 (2024):509-519,
https://doi.org/10.2298/SOS220624020N . .

TY  - JOUR
AU  - Mirković, Miljana M.
AU  - Kljajević, Ljiljana M.
AU  - Dolenec, Sabina
AU  - Nenadović, Miloš
AU  - Pavlović, Vladimir B.
AU  - Rajačić, Milica
AU  - Nenadović, Snežana S.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10092
AB  - Since recycled technologies usage is mandatory for environmental safety, and in this regard, it is important to examine new materials that can be used in construction and are primarily produced from fly ash. In addition to characteristics such as hardness and compressive strength, the given materials must also be radiologically and environmentally safe. The main concept of engineered geopolymer gel composites based on fly ash residues is focused on developing binder materials via gel formation processes that can replace ordinary cement materials. This study is unique in researching the potential use of fly ash from the Nikola Tesla thermal power plant in Serbia, where the hybrid geopolymeric materials synthesized from fly ash are experimentally examined with the addition 1 wt% and 2 wt% of polyvinyl alcohol (PVA). This paper aims to investigate the structural, morphological, mechanical, and radiological properties of hybrid materials with the addition of PVA and without additive in the period of ageing for 28 days at room temperature. The phase composition was investigated using X-ray powder diffraction (XRPD) analysis, while morphological characteristics of these materials were examined using scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDS). Vibrational spectra of obtained samples are investigated using diffuse reflectance infrared Fourier transform (DRIFT) and Fourier transform infrared (FTIR) techniques. The hardness and compressive strength are also examined, indicating that the 1 wt% addition in geopolymeric matrix results in the best mechanical properties. Radiological measurements of investigated all geopolymer samples show decreasing activity concentrations of radionuclides for 50% compared to fly ash.
T2  - Gels
T1  - Potential Usage of Hybrid Polymers Binders Based on Fly Ash with the Addition of PVA with Satisfying Mechanical and Radiological Properties
VL  - 7
IS  - 4
SP  - 270
DO  - 10.3390/gels7040270
ER  - 

@article{
author = "Mirković, Miljana M. and Kljajević, Ljiljana M. and Dolenec, Sabina and Nenadović, Miloš and Pavlović, Vladimir B. and Rajačić, Milica and Nenadović, Snežana S.",
year = "2021",
abstract = "Since recycled technologies usage is mandatory for environmental safety, and in this regard, it is important to examine new materials that can be used in construction and are primarily produced from fly ash. In addition to characteristics such as hardness and compressive strength, the given materials must also be radiologically and environmentally safe. The main concept of engineered geopolymer gel composites based on fly ash residues is focused on developing binder materials via gel formation processes that can replace ordinary cement materials. This study is unique in researching the potential use of fly ash from the Nikola Tesla thermal power plant in Serbia, where the hybrid geopolymeric materials synthesized from fly ash are experimentally examined with the addition 1 wt% and 2 wt% of polyvinyl alcohol (PVA). This paper aims to investigate the structural, morphological, mechanical, and radiological properties of hybrid materials with the addition of PVA and without additive in the period of ageing for 28 days at room temperature. The phase composition was investigated using X-ray powder diffraction (XRPD) analysis, while morphological characteristics of these materials were examined using scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDS). Vibrational spectra of obtained samples are investigated using diffuse reflectance infrared Fourier transform (DRIFT) and Fourier transform infrared (FTIR) techniques. The hardness and compressive strength are also examined, indicating that the 1 wt% addition in geopolymeric matrix results in the best mechanical properties. Radiological measurements of investigated all geopolymer samples show decreasing activity concentrations of radionuclides for 50% compared to fly ash.",
journal = "Gels",
title = "Potential Usage of Hybrid Polymers Binders Based on Fly Ash with the Addition of PVA with Satisfying Mechanical and Radiological Properties",
volume = "7",
number = "4",
pages = "270",
doi = "10.3390/gels7040270"
}

Mirković, M. M., Kljajević, L. M., Dolenec, S., Nenadović, M., Pavlović, V. B., Rajačić, M.,& Nenadović, S. S.. (2021). Potential Usage of Hybrid Polymers Binders Based on Fly Ash with the Addition of PVA with Satisfying Mechanical and Radiological Properties. in Gels, 7(4), 270.
https://doi.org/10.3390/gels7040270

Mirković MM, Kljajević LM, Dolenec S, Nenadović M, Pavlović VB, Rajačić M, Nenadović SS. Potential Usage of Hybrid Polymers Binders Based on Fly Ash with the Addition of PVA with Satisfying Mechanical and Radiological Properties. in Gels. 2021;7(4):270.
doi:10.3390/gels7040270 .

Mirković, Miljana M., Kljajević, Ljiljana M., Dolenec, Sabina, Nenadović, Miloš, Pavlović, Vladimir B., Rajačić, Milica, Nenadović, Snežana S., "Potential Usage of Hybrid Polymers Binders Based on Fly Ash with the Addition of PVA with Satisfying Mechanical and Radiological Properties" in Gels, 7, no. 4 (2021):270,
https://doi.org/10.3390/gels7040270 . .