TY  - JOUR
AU  - Kokunešoski, Maja
AU  - Janaćković, Đorđe
AU  - Kićević, Dušan
AU  - Ilić, Svetlana
AU  - Šaponjić, Aleksandra
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6468
AB  - Effect of methyl methacrylate (MMA) as a binder and heating treatment were investigated to improve green alumina compacts machinability. Properties of green compacts and their corresponding sintered samples prepared with and without MMA were compared. Investigation of green and sintered properties was performed on samples compacted at applied pressures up to 150 MPa. After pressing, samples with MMA were thermally treated at 115oC. The intention was to enhance the polymerization of MMA at a temperature a little higher than the glass transition temperature (Tg = 103°C) of poly (methyl methacrylate). Green compacts with MMA had higher green density values than those without MMA. Sintered samples with MMA had lower values of sintered density and higher values of total porosity; after sintering, relative linear shrinkage was around 15 % for the whole range of applied pressures. The possibility of easily machining the green compacts with MMA produces great possibilities for application in many fields.
AB  - Испитиван je утицај метил метакрилата (ММА) као везива као и утицај термичког третманана машинску обрадивост испресака од алумине. Упоређена су својства како код испресака од алумине припремљених са и без ММА тако и код њима одговарајућих синтерованих узорака. Испитивање особина испресака и синтерованих узоракаизведено је на узорцима који су испресовани на притисцима до 150 МРа. Након пресовања, узорци са ММА су термички третирани на 115о С са намером да ММА полимеризује на нешто вишој температури од температуре стакластог прелаза (Тg = 103°C) поли(метил метакрилата. Испресци са ММА имали су веће густине од испресака без ММА. Синтеровани узорци припремљени са ММА имали су ниже синтероване густине и већу укупну порозност, aнакон синтеровања, релативно линеарно скупљање је било око 15 % за цео опсег примењених притисака пресовања. Пробе машинске обрадљивости показале су да машинска обрада испресака са ММА има велике могућности за комерцијалну примену.
PB  - International Institute for the Science of Sintering (IISS)
T2  - Science of Sintering
T1  - The Effect of Acrylate on the Properties and Machinability of Alumina Ceramics
EP  - 113
IS  - 1
SP  - 103
VL  - 55
DO  - 10.2298/SOS2301103K
ER  - 

@article{
author = "Kokunešoski, Maja and Janaćković, Đorđe and Kićević, Dušan and Ilić, Svetlana and Šaponjić, Aleksandra",
year = "2023",
abstract = "Effect of methyl methacrylate (MMA) as a binder and heating treatment were investigated to improve green alumina compacts machinability. Properties of green compacts and their corresponding sintered samples prepared with and without MMA were compared. Investigation of green and sintered properties was performed on samples compacted at applied pressures up to 150 MPa. After pressing, samples with MMA were thermally treated at 115oC. The intention was to enhance the polymerization of MMA at a temperature a little higher than the glass transition temperature (Tg = 103°C) of poly (methyl methacrylate). Green compacts with MMA had higher green density values than those without MMA. Sintered samples with MMA had lower values of sintered density and higher values of total porosity; after sintering, relative linear shrinkage was around 15 % for the whole range of applied pressures. The possibility of easily machining the green compacts with MMA produces great possibilities for application in many fields., Испитиван je утицај метил метакрилата (ММА) као везива као и утицај термичког третманана машинску обрадивост испресака од алумине. Упоређена су својства како код испресака од алумине припремљених са и без ММА тако и код њима одговарајућих синтерованих узорака. Испитивање особина испресака и синтерованих узоракаизведено је на узорцима који су испресовани на притисцима до 150 МРа. Након пресовања, узорци са ММА су термички третирани на 115о С са намером да ММА полимеризује на нешто вишој температури од температуре стакластог прелаза (Тg = 103°C) поли(метил метакрилата. Испресци са ММА имали су веће густине од испресака без ММА. Синтеровани узорци припремљени са ММА имали су ниже синтероване густине и већу укупну порозност, aнакон синтеровања, релативно линеарно скупљање је било око 15 % за цео опсег примењених притисака пресовања. Пробе машинске обрадљивости показале су да машинска обрада испресака са ММА има велике могућности за комерцијалну примену.",
publisher = "International Institute for the Science of Sintering (IISS)",
journal = "Science of Sintering",
title = "The Effect of Acrylate on the Properties and Machinability of Alumina Ceramics",
pages = "113-103",
number = "1",
volume = "55",
doi = "10.2298/SOS2301103K"
}

Kokunešoski, M., Janaćković, Đ., Kićević, D., Ilić, S.,& Šaponjić, A.. (2023). The Effect of Acrylate on the Properties and Machinability of Alumina Ceramics. in Science of Sintering
International Institute for the Science of Sintering (IISS)., 55(1), 103-113.
https://doi.org/10.2298/SOS2301103K

Kokunešoski M, Janaćković Đ, Kićević D, Ilić S, Šaponjić A. The Effect of Acrylate on the Properties and Machinability of Alumina Ceramics. in Science of Sintering. 2023;55(1):103-113.
doi:10.2298/SOS2301103K .

Kokunešoski, Maja, Janaćković, Đorđe, Kićević, Dušan, Ilić, Svetlana, Šaponjić, Aleksandra, "The Effect of Acrylate on the Properties and Machinability of Alumina Ceramics" in Science of Sintering, 55, no. 1 (2023):103-113,
https://doi.org/10.2298/SOS2301103K . .

TY  - JOUR
AU  - Zivković, Lidija T. Izrael
AU  - Živković, Ljiljana
AU  - Babić, Biljana M.
AU  - Kokunešoski, Maja
AU  - Jokić, Bojan M.
AU  - Karadzic, Ivanka M.
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5758
AB  - Lipase from Candida rugosa was immobilized by adsorption onto laboratory prepared supports, silica SBA-15 and zirconia. The adsorption process was studied as a function of pH in terms of percent of adsorbed lipase, enzyme activity and zeta potential of support and enzyme. Several analytical approaches such as laser Doppler electrophoresis, Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM) showed that the lipase was successfully immobilized onto both supports. The zeta-potential data suggest that the adsorption efficiency does not depends on the sign but on the magnitude of the surface charge of adsorption partners, and therefore underline the importance of their dispersion stability. Adsorption to material surface altered enzyme characteristics. nu(max), for the lipase immobilized onto silica and zirconia were 4.8-fold and 3.6-fold lower than that of the free lipase, respectively. The Km showed no alteration of enzyme-substrate affinity on zirconia support, whereas the enzyme immobilized on silica had 3.6 times lower affinity. Thermostability at 60 degrees C of the lipase was improved 12-fold on zirconia and 4-fold on silica. Finally, in examining reusability, the immobilized lipase retained more than 90% of initial activity after eight reuses on both supports. (C) 2014 Elsevier B.V. All rights reserved.
PB  - Elsevier B.V.
T2  - Biochemical Engineering Journal
T1  - Immobilization of Candida rugosa lipase by adsorption onto biosafe meso/macroporous silica and zirconia
EP  - 83
SP  - 73
VL  - 93
DO  - 10.1016/j.bej.2014.09.012
ER  - 

@article{
author = "Zivković, Lidija T. Izrael and Živković, Ljiljana and Babić, Biljana M. and Kokunešoski, Maja and Jokić, Bojan M. and Karadzic, Ivanka M.",
year = "2015",
abstract = "Lipase from Candida rugosa was immobilized by adsorption onto laboratory prepared supports, silica SBA-15 and zirconia. The adsorption process was studied as a function of pH in terms of percent of adsorbed lipase, enzyme activity and zeta potential of support and enzyme. Several analytical approaches such as laser Doppler electrophoresis, Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM) showed that the lipase was successfully immobilized onto both supports. The zeta-potential data suggest that the adsorption efficiency does not depends on the sign but on the magnitude of the surface charge of adsorption partners, and therefore underline the importance of their dispersion stability. Adsorption to material surface altered enzyme characteristics. nu(max), for the lipase immobilized onto silica and zirconia were 4.8-fold and 3.6-fold lower than that of the free lipase, respectively. The Km showed no alteration of enzyme-substrate affinity on zirconia support, whereas the enzyme immobilized on silica had 3.6 times lower affinity. Thermostability at 60 degrees C of the lipase was improved 12-fold on zirconia and 4-fold on silica. Finally, in examining reusability, the immobilized lipase retained more than 90% of initial activity after eight reuses on both supports. (C) 2014 Elsevier B.V. All rights reserved.",
publisher = "Elsevier B.V.",
journal = "Biochemical Engineering Journal",
title = "Immobilization of Candida rugosa lipase by adsorption onto biosafe meso/macroporous silica and zirconia",
pages = "83-73",
volume = "93",
doi = "10.1016/j.bej.2014.09.012"
}

Zivković, L. T. I., Živković, L., Babić, B. M., Kokunešoski, M., Jokić, B. M.,& Karadzic, I. M.. (2015). Immobilization of Candida rugosa lipase by adsorption onto biosafe meso/macroporous silica and zirconia. in Biochemical Engineering Journal
Elsevier B.V.., 93, 73-83.
https://doi.org/10.1016/j.bej.2014.09.012

Zivković LTI, Živković L, Babić BM, Kokunešoski M, Jokić BM, Karadzic IM. Immobilization of Candida rugosa lipase by adsorption onto biosafe meso/macroporous silica and zirconia. in Biochemical Engineering Journal. 2015;93:73-83.
doi:10.1016/j.bej.2014.09.012 .

Zivković, Lidija T. Izrael, Živković, Ljiljana, Babić, Biljana M., Kokunešoski, Maja, Jokić, Bojan M., Karadzic, Ivanka M., "Immobilization of Candida rugosa lipase by adsorption onto biosafe meso/macroporous silica and zirconia" in Biochemical Engineering Journal, 93 (2015):73-83,
https://doi.org/10.1016/j.bej.2014.09.012 . .

TY  - JOUR
AU  - Nešić, Aleksandra
AU  - Kokunešoski, Maja
AU  - Ilić, Svetlana M.
AU  - Gordić, Milan V.
AU  - Ostojić, Sanja
AU  - Micić, Darko M.
AU  - Veličković, Sava J.
PY  - 2014
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5757
AB  - Manufacturing of synthetic composites consumes huge energy and their disposal at the end of the life cycle is very difficult since there is virtually no recycling option. Therefore, biocomposite materials have recently received considerable attention in academic research and industrial application compared to the synthetic composite materials due biodegradability, nontoxicity and economical point of view. Biocomposite membranes of highly methylated pectin and SBA-15, a form of mesoporous silica, were prepared by membrane casting. The amount of SBA-15 was 10%, 20% and 30% by membrane mass. These membranes were characterized by optical microscopy, FTIR, XRD, thermogravimetry, mechanical analysis and swelling in water, HCl, NaOH and methanol. The incorporation of SBA-15 in pectin matrix enhanced the stability of these membranes in all tested solutions, compared to the pure pectin membranes. The pectin/SBA photomicrographs contain rod-like domains which indicate the presence of SBA-15 in membrane. Mechanical analysis proves that incorporation of SBA-15 enhances the elasticity and tensile strength of pectin membranes. Thermogravimety in nitrogen has shown that the presence of SBA-15 in the membranes increased the onset temperatures of pectin degradation. The novel composite material represents promising way for practical membrane application. (C) 2014 Elsevier Ltd. All rights reserved.
PB  - Elsevier Ltd.
T2  - Composites: Part B: Engineering
T1  - Biocomposite membranes of highly methylated pectin and mesoporous silica SBA-15
EP  - 167
SP  - 162
VL  - 64
DO  - 10.1016/j.compositesb.2014.04.019
ER  - 

@article{
author = "Nešić, Aleksandra and Kokunešoski, Maja and Ilić, Svetlana M. and Gordić, Milan V. and Ostojić, Sanja and Micić, Darko M. and Veličković, Sava J.",
year = "2014",
abstract = "Manufacturing of synthetic composites consumes huge energy and their disposal at the end of the life cycle is very difficult since there is virtually no recycling option. Therefore, biocomposite materials have recently received considerable attention in academic research and industrial application compared to the synthetic composite materials due biodegradability, nontoxicity and economical point of view. Biocomposite membranes of highly methylated pectin and SBA-15, a form of mesoporous silica, were prepared by membrane casting. The amount of SBA-15 was 10%, 20% and 30% by membrane mass. These membranes were characterized by optical microscopy, FTIR, XRD, thermogravimetry, mechanical analysis and swelling in water, HCl, NaOH and methanol. The incorporation of SBA-15 in pectin matrix enhanced the stability of these membranes in all tested solutions, compared to the pure pectin membranes. The pectin/SBA photomicrographs contain rod-like domains which indicate the presence of SBA-15 in membrane. Mechanical analysis proves that incorporation of SBA-15 enhances the elasticity and tensile strength of pectin membranes. Thermogravimety in nitrogen has shown that the presence of SBA-15 in the membranes increased the onset temperatures of pectin degradation. The novel composite material represents promising way for practical membrane application. (C) 2014 Elsevier Ltd. All rights reserved.",
publisher = "Elsevier Ltd.",
journal = "Composites: Part B: Engineering",
title = "Biocomposite membranes of highly methylated pectin and mesoporous silica SBA-15",
pages = "167-162",
volume = "64",
doi = "10.1016/j.compositesb.2014.04.019"
}

Nešić, A., Kokunešoski, M., Ilić, S. M., Gordić, M. V., Ostojić, S., Micić, D. M.,& Veličković, S. J.. (2014). Biocomposite membranes of highly methylated pectin and mesoporous silica SBA-15. in Composites: Part B: Engineering
Elsevier Ltd.., 64, 162-167.
https://doi.org/10.1016/j.compositesb.2014.04.019

Nešić A, Kokunešoski M, Ilić SM, Gordić MV, Ostojić S, Micić DM, Veličković SJ. Biocomposite membranes of highly methylated pectin and mesoporous silica SBA-15. in Composites: Part B: Engineering. 2014;64:162-167.
doi:10.1016/j.compositesb.2014.04.019 .

Nešić, Aleksandra, Kokunešoski, Maja, Ilić, Svetlana M., Gordić, Milan V., Ostojić, Sanja, Micić, Darko M., Veličković, Sava J., "Biocomposite membranes of highly methylated pectin and mesoporous silica SBA-15" in Composites: Part B: Engineering, 64 (2014):162-167,
https://doi.org/10.1016/j.compositesb.2014.04.019 . .