TY  - CONF
AU  - Čokeša, Đuro
AU  - Marković, Mirjana
AU  - Potkonjak, Nebojša
AU  - Kaluđerović, Branka
AU  - Radmanović, Svjetlana
AU  - Šerbula, Snežana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12847
AB  - Arsenite–humic acid-binding process was investigated using the Isothermal Titration Calorimetry(ITC). The ITC data were successfully (R2=0.996-0.936) interpreted by applying the MNIS model,enabling thermodynamic parameters to be determined. The MNIS model was adjusted to the arsenite–HA binding process assuming hydrogen bonding as the dominant type of interaction in the system.Negative enthalpy change values indicated the arsenite–HAs binding as an exothermic process.Negative ΔG values (-(27.85-26.83) kJ mol-1) pointed out to spontaneous binding reaction, leading tothe formation of the arsenite–HA complexes. High binding constants values ((7.57-5.02)105 M-1)clearly demonstrated pronounced binding affinity. As ΔS values (0.041-0.027) kJ mol-1 K-1) wereapparently positive, but close to zero, and ΔH>ΔS, the reaction could be considered enthalpy driven.Reaction heats and H values (-(18.96-15.64) kJ mol-1) confirmed hydrogen bonds as the mostascendant interaction type in the arsenite–HA complex. Thermodynamic and reaction parametersclearly indicated that arsenite–HA complexes are formed at common soil pH values, confirming thepossible influence of humic acids on increased As mobility, and its reduced bioavailability.
PB  - Bor : University of Belgrade, Technical Faculty in Bor
C3  - EcoTER’22 : 29th International Conference Ecological Truth and Environmental Research : Proceedings
T1  - Arsenite–soil humic acid binding by isothermal titration calorimetry: Thermodynamics and MNIS model
SP  - 121
EP  - 126
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12847
ER  - 

@conference{
author = "Čokeša, Đuro and Marković, Mirjana and Potkonjak, Nebojša and Kaluđerović, Branka and Radmanović, Svjetlana and Šerbula, Snežana",
year = "2023",
abstract = "Arsenite–humic acid-binding process was investigated using the Isothermal Titration Calorimetry(ITC). The ITC data were successfully (R2=0.996-0.936) interpreted by applying the MNIS model,enabling thermodynamic parameters to be determined. The MNIS model was adjusted to the arsenite–HA binding process assuming hydrogen bonding as the dominant type of interaction in the system.Negative enthalpy change values indicated the arsenite–HAs binding as an exothermic process.Negative ΔG values (-(27.85-26.83) kJ mol-1) pointed out to spontaneous binding reaction, leading tothe formation of the arsenite–HA complexes. High binding constants values ((7.57-5.02)105 M-1)clearly demonstrated pronounced binding affinity. As ΔS values (0.041-0.027) kJ mol-1 K-1) wereapparently positive, but close to zero, and ΔH>ΔS, the reaction could be considered enthalpy driven.Reaction heats and H values (-(18.96-15.64) kJ mol-1) confirmed hydrogen bonds as the mostascendant interaction type in the arsenite–HA complex. Thermodynamic and reaction parametersclearly indicated that arsenite–HA complexes are formed at common soil pH values, confirming thepossible influence of humic acids on increased As mobility, and its reduced bioavailability.",
publisher = "Bor : University of Belgrade, Technical Faculty in Bor",
journal = "EcoTER’22 : 29th International Conference Ecological Truth and Environmental Research : Proceedings",
title = "Arsenite–soil humic acid binding by isothermal titration calorimetry: Thermodynamics and MNIS model",
pages = "121-126",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12847"
}

Čokeša, Đ., Marković, M., Potkonjak, N., Kaluđerović, B., Radmanović, S.,& Šerbula, S.. (2023). Arsenite–soil humic acid binding by isothermal titration calorimetry: Thermodynamics and MNIS model. in EcoTER’22 : 29th International Conference Ecological Truth and Environmental Research : Proceedings
Bor : University of Belgrade, Technical Faculty in Bor., 121-126.
https://hdl.handle.net/21.15107/rcub_vinar_12847

Čokeša Đ, Marković M, Potkonjak N, Kaluđerović B, Radmanović S, Šerbula S. Arsenite–soil humic acid binding by isothermal titration calorimetry: Thermodynamics and MNIS model. in EcoTER’22 : 29th International Conference Ecological Truth and Environmental Research : Proceedings. 2023;:121-126.
https://hdl.handle.net/21.15107/rcub_vinar_12847 .

Čokeša, Đuro, Marković, Mirjana, Potkonjak, Nebojša, Kaluđerović, Branka, Radmanović, Svjetlana, Šerbula, Snežana, "Arsenite–soil humic acid binding by isothermal titration calorimetry: Thermodynamics and MNIS model" in EcoTER’22 : 29th International Conference Ecological Truth and Environmental Research : Proceedings (2023):121-126,
https://hdl.handle.net/21.15107/rcub_vinar_12847 .

TY  - JOUR
AU  - Jovanović, Uroš D.
AU  - Marković, Mirjana
AU  - Čokeša, Đuro
AU  - Živković, Nikola V.
AU  - Radmanović, Svjetlana B.
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10351
AB  - The main goal of this work was to estimate the influence of carboxyl and phenolic groups, as well as aromatic, aliphatic and polysaccharide components, on the soil humic acids (HA) self-aggregation process. Soil HAs (leptosol and regosol) were separated using base resin getting fractions with different functional group contents. Blocking of carboxyl groups was performed using the esterification procedure to estimate the participation of each functional group in the HA aggregation. The presence of HA structural components was evaluated by potentiometric titration and ATR-FTIR. The aggregation was monitored at pH 3 using dynamic light scattering. Results indicated that the higher group content, the HA aggregation is less pronounced. A significant positive correlation of aliphatic C and aggregate size revealed their dominant influence in the HA self-aggregation. A lower abundance of aliphatic C in HA fractions could be considered as not sufficient to start the process. An increase of aromatic C in esters likely pointed out to its participation in hydrophobic bonding and, consequently, more pronounced aggregation. The relation of HA self-aggregate size with carboxyl and phenolic group, as well as aliphatic C, at low pH, could be considered universal regardless of the structural characteristics of the original or modified HA forms.
T2  - Journal of the Serbian Chemical Society
T1  - Self-aggregation of soil humic acids with respect to their structural characteristics
VL  - 87
IS  - 6
SP  - 761
EP  - 773
DO  - 10.2298/JSC211125010J
ER  - 

@article{
author = "Jovanović, Uroš D. and Marković, Mirjana and Čokeša, Đuro and Živković, Nikola V. and Radmanović, Svjetlana B.",
year = "2022",
abstract = "The main goal of this work was to estimate the influence of carboxyl and phenolic groups, as well as aromatic, aliphatic and polysaccharide components, on the soil humic acids (HA) self-aggregation process. Soil HAs (leptosol and regosol) were separated using base resin getting fractions with different functional group contents. Blocking of carboxyl groups was performed using the esterification procedure to estimate the participation of each functional group in the HA aggregation. The presence of HA structural components was evaluated by potentiometric titration and ATR-FTIR. The aggregation was monitored at pH 3 using dynamic light scattering. Results indicated that the higher group content, the HA aggregation is less pronounced. A significant positive correlation of aliphatic C and aggregate size revealed their dominant influence in the HA self-aggregation. A lower abundance of aliphatic C in HA fractions could be considered as not sufficient to start the process. An increase of aromatic C in esters likely pointed out to its participation in hydrophobic bonding and, consequently, more pronounced aggregation. The relation of HA self-aggregate size with carboxyl and phenolic group, as well as aliphatic C, at low pH, could be considered universal regardless of the structural characteristics of the original or modified HA forms.",
journal = "Journal of the Serbian Chemical Society",
title = "Self-aggregation of soil humic acids with respect to their structural characteristics",
volume = "87",
number = "6",
pages = "761-773",
doi = "10.2298/JSC211125010J"
}

Jovanović, U. D., Marković, M., Čokeša, Đ., Živković, N. V.,& Radmanović, S. B.. (2022). Self-aggregation of soil humic acids with respect to their structural characteristics. in Journal of the Serbian Chemical Society, 87(6), 761-773.
https://doi.org/10.2298/JSC211125010J

Jovanović UD, Marković M, Čokeša Đ, Živković NV, Radmanović SB. Self-aggregation of soil humic acids with respect to their structural characteristics. in Journal of the Serbian Chemical Society. 2022;87(6):761-773.
doi:10.2298/JSC211125010J .

Jovanović, Uroš D., Marković, Mirjana, Čokeša, Đuro, Živković, Nikola V., Radmanović, Svjetlana B., "Self-aggregation of soil humic acids with respect to their structural characteristics" in Journal of the Serbian Chemical Society, 87, no. 6 (2022):761-773,
https://doi.org/10.2298/JSC211125010J . .

TY  - CONF
AU  - Krstić, Sanja S.
AU  - Dodevski, Vladimir
AU  - Čokeša, Đuro
AU  - Devečerski, Aleksandar
AU  - Vujasin, Radojka
AU  - Kumrić, Ksenija
AU  - Kaluđerović, Branka V.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10781
AB  - Carbon material with active surface properties have been synthesized by hydrothermal method from fructose using 40% and 80% phosphoric acid (H3 PO4 ) solution, at temperature of 260°C and fructose concentration of 2M. The aim of this investigation was active carbon material synthesis which is completed by one step reaction, which was not the case in our previous works. Thus, compared with other samples from our works, this way is more economic and faster since both reaction of carbonization and activation was finished in one step. The hydrothermal process, in general, includes heat treatment of carbohydrate solutions under autogenous pressure at low temperatures (150–260 °C). Obtained solid carbon material has uniform morphology, amorphous structure and high content of oxygen functional groups. Prepared active carbon material is made up of spherical microsphere particles with the diameter in the range of 0.6-2.7 μm. The morphology and surface properties of obtained material were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectra. Adsorption and desorption isotherms of N2 were measured on carbon containing material at -196 °C using the gravimetric McBain method. Adsorption from aqueous solutions of Methylene Blue (MB) onto prepared carbon material was conducted by changing concentration of MB from 200-500mg/dm3 . The best fit of the kinetic results was achieved by a pseudo second-order equation. Also, this nature of material is applicable in other systems regarding environmental protection and dye pollution prevention.
PB  - Belgrade : Serbian Ceramic Society
C3  - Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade
T1  - Preparation and Characterization Of Active Carbon Microspheres Obtained From Fructose And Adsorption Application
SP  - 38
UR  - https://hdl.handle.net/21.15107/rcub_vinar_10781
ER  - 

@conference{
author = "Krstić, Sanja S. and Dodevski, Vladimir and Čokeša, Đuro and Devečerski, Aleksandar and Vujasin, Radojka and Kumrić, Ksenija and Kaluđerović, Branka V.",
year = "2021",
abstract = "Carbon material with active surface properties have been synthesized by hydrothermal method from fructose using 40% and 80% phosphoric acid (H3 PO4 ) solution, at temperature of 260°C and fructose concentration of 2M. The aim of this investigation was active carbon material synthesis which is completed by one step reaction, which was not the case in our previous works. Thus, compared with other samples from our works, this way is more economic and faster since both reaction of carbonization and activation was finished in one step. The hydrothermal process, in general, includes heat treatment of carbohydrate solutions under autogenous pressure at low temperatures (150–260 °C). Obtained solid carbon material has uniform morphology, amorphous structure and high content of oxygen functional groups. Prepared active carbon material is made up of spherical microsphere particles with the diameter in the range of 0.6-2.7 μm. The morphology and surface properties of obtained material were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectra. Adsorption and desorption isotherms of N2 were measured on carbon containing material at -196 °C using the gravimetric McBain method. Adsorption from aqueous solutions of Methylene Blue (MB) onto prepared carbon material was conducted by changing concentration of MB from 200-500mg/dm3 . The best fit of the kinetic results was achieved by a pseudo second-order equation. Also, this nature of material is applicable in other systems regarding environmental protection and dye pollution prevention.",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade",
title = "Preparation and Characterization Of Active Carbon Microspheres Obtained From Fructose And Adsorption Application",
pages = "38",
url = "https://hdl.handle.net/21.15107/rcub_vinar_10781"
}

Krstić, S. S., Dodevski, V., Čokeša, Đ., Devečerski, A., Vujasin, R., Kumrić, K.,& Kaluđerović, B. V.. (2021). Preparation and Characterization Of Active Carbon Microspheres Obtained From Fructose And Adsorption Application. in Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade
Belgrade : Serbian Ceramic Society., 38.
https://hdl.handle.net/21.15107/rcub_vinar_10781

Krstić SS, Dodevski V, Čokeša Đ, Devečerski A, Vujasin R, Kumrić K, Kaluđerović BV. Preparation and Characterization Of Active Carbon Microspheres Obtained From Fructose And Adsorption Application. in Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade. 2021;:38.
https://hdl.handle.net/21.15107/rcub_vinar_10781 .

Krstić, Sanja S., Dodevski, Vladimir, Čokeša, Đuro, Devečerski, Aleksandar, Vujasin, Radojka, Kumrić, Ksenija, Kaluđerović, Branka V., "Preparation and Characterization Of Active Carbon Microspheres Obtained From Fructose And Adsorption Application" in Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade (2021):38,
https://hdl.handle.net/21.15107/rcub_vinar_10781 .

TY  - CONF
AU  - Krstić, Sanja S.
AU  - Dodevski, Vladimir
AU  - Čokeša, Đuro
AU  - Devečerski, Aleksandar
AU  - Vujasin, Radojka
AU  - Kumrić, Ksenija
AU  - Kaluđerović, Branka V.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10841
AB  - A carbon-rich solid product has been synthesized by hydrothermal treatment from fructose with phosphoric acid (H3 PO4 ) at temperature of 250°C and pH value of 0.65. The concentration of the precursor was constant, i.e. 2M of fructose in form of aqueous solution. The formation of the carbon-rich solid material through the hydrothermal carbonization of fructose is the consequence of dehydration reactions. Obtained carbon material is made of spherical micrometer-sized particles with the diameter in the 4-7 μm. The structure and surface chemical properties of obtained material were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectra. Investigation of surface area was determined by gravimetric McBain method where adsorption and desorption isotherms of N2 were measured on carbon material at -196 °C. Adsorption of Methylene Blue (MB) onto prepared carbon material were conducted by changing concentration of MB from 200-500 mg/dm 3 from aqueous solutions of investigated dye. Kinetic results were determined by a pseudo second-order equation.
PB  - Belgrade : Serbian Ceramic Society
C3  - Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade
T1  - Preparation and Characterization of Active Carbon Microspheres Obtained from Fructose and Adsorption Application
SP  - 81
UR  - https://hdl.handle.net/21.15107/rcub_vinar_10841
ER  - 

@conference{
author = "Krstić, Sanja S. and Dodevski, Vladimir and Čokeša, Đuro and Devečerski, Aleksandar and Vujasin, Radojka and Kumrić, Ksenija and Kaluđerović, Branka V.",
year = "2021",
abstract = "A carbon-rich solid product has been synthesized by hydrothermal treatment from fructose with phosphoric acid (H3 PO4 ) at temperature of 250°C and pH value of 0.65. The concentration of the precursor was constant, i.e. 2M of fructose in form of aqueous solution. The formation of the carbon-rich solid material through the hydrothermal carbonization of fructose is the consequence of dehydration reactions. Obtained carbon material is made of spherical micrometer-sized particles with the diameter in the 4-7 μm. The structure and surface chemical properties of obtained material were characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectra. Investigation of surface area was determined by gravimetric McBain method where adsorption and desorption isotherms of N2 were measured on carbon material at -196 °C. Adsorption of Methylene Blue (MB) onto prepared carbon material were conducted by changing concentration of MB from 200-500 mg/dm 3 from aqueous solutions of investigated dye. Kinetic results were determined by a pseudo second-order equation.",
publisher = "Belgrade : Serbian Ceramic Society",
journal = "Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade",
title = "Preparation and Characterization of Active Carbon Microspheres Obtained from Fructose and Adsorption Application",
pages = "81",
url = "https://hdl.handle.net/21.15107/rcub_vinar_10841"
}

Krstić, S. S., Dodevski, V., Čokeša, Đ., Devečerski, A., Vujasin, R., Kumrić, K.,& Kaluđerović, B. V.. (2021). Preparation and Characterization of Active Carbon Microspheres Obtained from Fructose and Adsorption Application. in Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade
Belgrade : Serbian Ceramic Society., 81.
https://hdl.handle.net/21.15107/rcub_vinar_10841

Krstić SS, Dodevski V, Čokeša Đ, Devečerski A, Vujasin R, Kumrić K, Kaluđerović BV. Preparation and Characterization of Active Carbon Microspheres Obtained from Fructose and Adsorption Application. in Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade. 2021;:81.
https://hdl.handle.net/21.15107/rcub_vinar_10841 .

Krstić, Sanja S., Dodevski, Vladimir, Čokeša, Đuro, Devečerski, Aleksandar, Vujasin, Radojka, Kumrić, Ksenija, Kaluđerović, Branka V., "Preparation and Characterization of Active Carbon Microspheres Obtained from Fructose and Adsorption Application" in Advanced Ceramics and Application : 9th Serbian Ceramic Society Conference : program and the book of abstracts; September 20-21, 2021; Belgrade (2021):81,
https://hdl.handle.net/21.15107/rcub_vinar_10841 .

TY  - JOUR
AU  - Radmanović, Svjetlana B.
AU  - Marković, Mirjana
AU  - Jovanović, Uroš D.
AU  - Gajić-Kvaščev, Maja
AU  - Čokeša, Đuro
AU  - Lilić, Jasmina
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9020
AB  - Part of Cu post flotation tailings of Serbia ZiJin Bor Copper, Serbia, was reclaimed by restoration of top soil with arable soils, and revegetation in 1991. Humic acids isolated from these Technosols were investigated to find out if their properties underwent any changes since reclamation. Two groups of control samples were used. Elemental composition (CHNS analysis) falls within the range of average soil humic acids. Humic acids belong to the type B pointing out to its lower humification degree (UV?Vis). Relative abundances of functional groups are ranged as follows: polysaccharide C ??aromatic C > carboxyl C > OH group > aliphatic C. Aromaticity indexes are low, 1.88? 3.25 (ATR-FTIR). Basic units at pH 10 are in the 11.7?26.8 nm range. Pronounced reaggregation (1462-?5218 nm) at pH 3 points out to less expressed humic acid sol stability, as well as to increase in aromatic condensation degree (dynamic light scattering). No significant changes have occurred in technosol humic acids since the recultivation, confirming stability of their properties over time (PCA). Nevertheless, humic acids from very strongly acidic Technosols show higher humifycation degree possibly originating from arable soils used in reclamation, but more likely from low soil pH and low litter input, results of unsuccessful reclamation.
T2  - Journal of the Serbian Chemical Society
T1  - Properties of humic acids from copper tailings 20 years after reclamation
VL  - 85
IS  - 3
SP  - 407
EP  - 419
DO  - 10.2298/JSC190717112R
ER  - 

@article{
author = "Radmanović, Svjetlana B. and Marković, Mirjana and Jovanović, Uroš D. and Gajić-Kvaščev, Maja and Čokeša, Đuro and Lilić, Jasmina",
year = "2020",
abstract = "Part of Cu post flotation tailings of Serbia ZiJin Bor Copper, Serbia, was reclaimed by restoration of top soil with arable soils, and revegetation in 1991. Humic acids isolated from these Technosols were investigated to find out if their properties underwent any changes since reclamation. Two groups of control samples were used. Elemental composition (CHNS analysis) falls within the range of average soil humic acids. Humic acids belong to the type B pointing out to its lower humification degree (UV?Vis). Relative abundances of functional groups are ranged as follows: polysaccharide C ??aromatic C > carboxyl C > OH group > aliphatic C. Aromaticity indexes are low, 1.88? 3.25 (ATR-FTIR). Basic units at pH 10 are in the 11.7?26.8 nm range. Pronounced reaggregation (1462-?5218 nm) at pH 3 points out to less expressed humic acid sol stability, as well as to increase in aromatic condensation degree (dynamic light scattering). No significant changes have occurred in technosol humic acids since the recultivation, confirming stability of their properties over time (PCA). Nevertheless, humic acids from very strongly acidic Technosols show higher humifycation degree possibly originating from arable soils used in reclamation, but more likely from low soil pH and low litter input, results of unsuccessful reclamation.",
journal = "Journal of the Serbian Chemical Society",
title = "Properties of humic acids from copper tailings 20 years after reclamation",
volume = "85",
number = "3",
pages = "407-419",
doi = "10.2298/JSC190717112R"
}

Radmanović, S. B., Marković, M., Jovanović, U. D., Gajić-Kvaščev, M., Čokeša, Đ.,& Lilić, J.. (2020). Properties of humic acids from copper tailings 20 years after reclamation. in Journal of the Serbian Chemical Society, 85(3), 407-419.
https://doi.org/10.2298/JSC190717112R

Radmanović SB, Marković M, Jovanović UD, Gajić-Kvaščev M, Čokeša Đ, Lilić J. Properties of humic acids from copper tailings 20 years after reclamation. in Journal of the Serbian Chemical Society. 2020;85(3):407-419.
doi:10.2298/JSC190717112R .

Radmanović, Svjetlana B., Marković, Mirjana, Jovanović, Uroš D., Gajić-Kvaščev, Maja, Čokeša, Đuro, Lilić, Jasmina, "Properties of humic acids from copper tailings 20 years after reclamation" in Journal of the Serbian Chemical Society, 85, no. 3 (2020):407-419,
https://doi.org/10.2298/JSC190717112R . .

TY  - JOUR
AU  - Milanović, Srđan
AU  - Potkonjak, Nebojša I.
AU  - Mandušić, Vesna
AU  - Čokeša, Đuro
AU  - Hranisavljević, Jelena
AU  - Kaluđerović, Branka V.
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8975
AB  - Carbonaceous materials as well as its form functionalized with metallic silver have been prepared by hydrothermal carbonization of fructose. Results are presented to show that nanostructured silver was obtained through the functionalization process. The carbonaceous materials were characterized by: nitrogen adsorption/desorption measurement, XRD, SEM/EDS and FTIR. Samples functionalized with silver were analyzed by: XRD and SEM/EDS. The XRD analysis showed that the carbonaceous materials functionalized with silver by hydrothermal carbonization process were successfully performed. Size of silver particles was found to be approximately 32 nm, indicating formation of nanostructure. All samples were tested as an antimicrobial agent for water disinfection. Presence of nanostructured silver in the sample containing 1 mg/mL carbonaceous materials significantly decreased the number of CFU (dCFU = 97.33 %) if compared to the same sample containing the same amount of carbonaceous materials but without of silver (dCFU 65.33 %).
T2  - Science of Sintering
T1  - Antimicrobial effects of carbonaceous material functionalized with silver
VL  - 52
IS  - 1
SP  - 87
EP  - 95
DO  - 10.2298/SOS2001087M
ER  - 

@article{
author = "Milanović, Srđan and Potkonjak, Nebojša I. and Mandušić, Vesna and Čokeša, Đuro and Hranisavljević, Jelena and Kaluđerović, Branka V.",
year = "2020",
abstract = "Carbonaceous materials as well as its form functionalized with metallic silver have been prepared by hydrothermal carbonization of fructose. Results are presented to show that nanostructured silver was obtained through the functionalization process. The carbonaceous materials were characterized by: nitrogen adsorption/desorption measurement, XRD, SEM/EDS and FTIR. Samples functionalized with silver were analyzed by: XRD and SEM/EDS. The XRD analysis showed that the carbonaceous materials functionalized with silver by hydrothermal carbonization process were successfully performed. Size of silver particles was found to be approximately 32 nm, indicating formation of nanostructure. All samples were tested as an antimicrobial agent for water disinfection. Presence of nanostructured silver in the sample containing 1 mg/mL carbonaceous materials significantly decreased the number of CFU (dCFU = 97.33 %) if compared to the same sample containing the same amount of carbonaceous materials but without of silver (dCFU 65.33 %).",
journal = "Science of Sintering",
title = "Antimicrobial effects of carbonaceous material functionalized with silver",
volume = "52",
number = "1",
pages = "87-95",
doi = "10.2298/SOS2001087M"
}

Milanović, S., Potkonjak, N. I., Mandušić, V., Čokeša, Đ., Hranisavljević, J.,& Kaluđerović, B. V.. (2020). Antimicrobial effects of carbonaceous material functionalized with silver. in Science of Sintering, 52(1), 87-95.
https://doi.org/10.2298/SOS2001087M

Milanović S, Potkonjak NI, Mandušić V, Čokeša Đ, Hranisavljević J, Kaluđerović BV. Antimicrobial effects of carbonaceous material functionalized with silver. in Science of Sintering. 2020;52(1):87-95.
doi:10.2298/SOS2001087M .

Milanović, Srđan, Potkonjak, Nebojša I., Mandušić, Vesna, Čokeša, Đuro, Hranisavljević, Jelena, Kaluđerović, Branka V., "Antimicrobial effects of carbonaceous material functionalized with silver" in Science of Sintering, 52, no. 1 (2020):87-95,
https://doi.org/10.2298/SOS2001087M . .

TY  - JOUR
AU  - Savić, Andrija B.
AU  - Čokeša, Đuro
AU  - Savić-Biserčić, Marjetka
AU  - Janković-Častvan, Ivona
AU  - Petrović, Rada
AU  - Živković, Ljiljana
PY  - 2019
UR  - https://linkinghub.elsevier.com/retrieve/pii/S0921883119301529
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8221
AB  - Natural filtration material tuff (T) was modified by coating with nano-sized magnetite. The grain fraction of 0.6–1.9 mm was submitted to hydrothermal synthesis of magnetite. Thus formed magnetite modified tuff (MMT) was characterized in terms of Fe-content, N2 adsorption- desorption isotherm, SEM, zeta potential-pH analyses and adsorption behavior towards phosphates/arsenates in batch and column conditions. Elemental analysis showed that 36.54 mg g−1 of magnetite was attached to the porous tuff grains. This modification changed pore structure and specific surface area. An increase of cca 35% in Sp value was obtained. Batch experiments proved that MMT was 4-5 times more efficient in removal of phosphates/arsenates than non-modified T. The maximum sorption capacities of phosphates calculated based on Langmuir equation were 0.45 and 1.91 mg g−1, while those for arsenate were 0.551 m g−1 and 2.36 mg g−1 for T and MMT, respectively. The intra-particle diffusion model was the most suited for describing the adsorption process of phosphate and arsenate onto MMT. Fixed-bed column data corroborated batch results, i.e. MMT was 6 times superior in contaminant adsorption than T. Modification with magnetite improved T potential for usage in water treatment applications: its filtration ability remained unchanged, while adsorption capacity for phosphates/arsenates removal was improved. © 2019 The Society of Powder Technology Japan
T2  - Advanced Powder Technology
T1  - Multifunctional use of magnetite-coated tuff grains in water treatment: Removal of arsenates and phosphates
VL  - 30
IS  - 8
SP  - 1687
EP  - 1695
DO  - 10.1016/j.apt.2019.05.020
ER  - 

@article{
author = "Savić, Andrija B. and Čokeša, Đuro and Savić-Biserčić, Marjetka and Janković-Častvan, Ivona and Petrović, Rada and Živković, Ljiljana",
year = "2019",
abstract = "Natural filtration material tuff (T) was modified by coating with nano-sized magnetite. The grain fraction of 0.6–1.9 mm was submitted to hydrothermal synthesis of magnetite. Thus formed magnetite modified tuff (MMT) was characterized in terms of Fe-content, N2 adsorption- desorption isotherm, SEM, zeta potential-pH analyses and adsorption behavior towards phosphates/arsenates in batch and column conditions. Elemental analysis showed that 36.54 mg g−1 of magnetite was attached to the porous tuff grains. This modification changed pore structure and specific surface area. An increase of cca 35% in Sp value was obtained. Batch experiments proved that MMT was 4-5 times more efficient in removal of phosphates/arsenates than non-modified T. The maximum sorption capacities of phosphates calculated based on Langmuir equation were 0.45 and 1.91 mg g−1, while those for arsenate were 0.551 m g−1 and 2.36 mg g−1 for T and MMT, respectively. The intra-particle diffusion model was the most suited for describing the adsorption process of phosphate and arsenate onto MMT. Fixed-bed column data corroborated batch results, i.e. MMT was 6 times superior in contaminant adsorption than T. Modification with magnetite improved T potential for usage in water treatment applications: its filtration ability remained unchanged, while adsorption capacity for phosphates/arsenates removal was improved. © 2019 The Society of Powder Technology Japan",
journal = "Advanced Powder Technology",
title = "Multifunctional use of magnetite-coated tuff grains in water treatment: Removal of arsenates and phosphates",
volume = "30",
number = "8",
pages = "1687-1695",
doi = "10.1016/j.apt.2019.05.020"
}

Savić, A. B., Čokeša, Đ., Savić-Biserčić, M., Janković-Častvan, I., Petrović, R.,& Živković, L.. (2019). Multifunctional use of magnetite-coated tuff grains in water treatment: Removal of arsenates and phosphates. in Advanced Powder Technology, 30(8), 1687-1695.
https://doi.org/10.1016/j.apt.2019.05.020

Savić AB, Čokeša Đ, Savić-Biserčić M, Janković-Častvan I, Petrović R, Živković L. Multifunctional use of magnetite-coated tuff grains in water treatment: Removal of arsenates and phosphates. in Advanced Powder Technology. 2019;30(8):1687-1695.
doi:10.1016/j.apt.2019.05.020 .

Savić, Andrija B., Čokeša, Đuro, Savić-Biserčić, Marjetka, Janković-Častvan, Ivona, Petrović, Rada, Živković, Ljiljana, "Multifunctional use of magnetite-coated tuff grains in water treatment: Removal of arsenates and phosphates" in Advanced Powder Technology, 30, no. 8 (2019):1687-1695,
https://doi.org/10.1016/j.apt.2019.05.020 . .

TY  - JOUR
AU  - Savić, Andrija B.
AU  - Čokeša, Đuro
AU  - Lazarevic, Slavica
AU  - Jokić, Bojan M.
AU  - Janaćković, Đorđe T.
AU  - Petrović, Rada
AU  - Živković, Ljiljana
PY  - 2016
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1262
AB  - This study demonstrates that PEG-assisted hydrothermal synthesis provides a convenient and eco-friendly route to fabrication of mesoporous magnetite with enhanced capacity for phosphate removal, excellent potential for magnetic separation and good reusability. Adsorption of phosphate onto 4 laboratory prepared magnetite powders was investigated in a systematic manner. Powders were synthesized in poly(ethylene) glycol-free or assisted conditions (PEGs 400 and 20,000 at varied PEG/water ratio), and characterized in terms of crystalline structure, and magnetic, morphological, textural, and acid-base properties. PEG acted as a powerful pore forming agent, the PEG/water ratio being the key factor in developing the surface area and mesoporosity of magnetite. Uptake capacity for phosphates increased with an increase in surface area and pore volume. PEG 20,000 at a ratio of 3:1 gave the best result. This mesoporous (D-max = 11 nm), nano-scale ( LT 10 nm) magnetite was ca. 9 times more efficient than nonporous micrometric powder derived from PEG-free synthesis (Langmuir maximum capacity, q(m) = 26.2 vs. 3.0 mg g(-1)). The adsorption was pH-dependent, in accord with variations in zeta potential of magnetite. Opposite shifts of isoelectric point and point of zero charge confirmed specific adsorption of phosphates at water/magnetite interface which proceeded via replacement of surface hydroxyls and sulfates. (C) 2016 Elsevier B.V. All rights reserved.
T2  - Powder Technology
T1  - Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process
VL  - 301
SP  - 511
EP  - 519
DO  - 10.1016/j.powtec.2016.06.028
ER  - 

@article{
author = "Savić, Andrija B. and Čokeša, Đuro and Lazarevic, Slavica and Jokić, Bojan M. and Janaćković, Đorđe T. and Petrović, Rada and Živković, Ljiljana",
year = "2016",
abstract = "This study demonstrates that PEG-assisted hydrothermal synthesis provides a convenient and eco-friendly route to fabrication of mesoporous magnetite with enhanced capacity for phosphate removal, excellent potential for magnetic separation and good reusability. Adsorption of phosphate onto 4 laboratory prepared magnetite powders was investigated in a systematic manner. Powders were synthesized in poly(ethylene) glycol-free or assisted conditions (PEGs 400 and 20,000 at varied PEG/water ratio), and characterized in terms of crystalline structure, and magnetic, morphological, textural, and acid-base properties. PEG acted as a powerful pore forming agent, the PEG/water ratio being the key factor in developing the surface area and mesoporosity of magnetite. Uptake capacity for phosphates increased with an increase in surface area and pore volume. PEG 20,000 at a ratio of 3:1 gave the best result. This mesoporous (D-max = 11 nm), nano-scale ( LT 10 nm) magnetite was ca. 9 times more efficient than nonporous micrometric powder derived from PEG-free synthesis (Langmuir maximum capacity, q(m) = 26.2 vs. 3.0 mg g(-1)). The adsorption was pH-dependent, in accord with variations in zeta potential of magnetite. Opposite shifts of isoelectric point and point of zero charge confirmed specific adsorption of phosphates at water/magnetite interface which proceeded via replacement of surface hydroxyls and sulfates. (C) 2016 Elsevier B.V. All rights reserved.",
journal = "Powder Technology",
title = "Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process",
volume = "301",
pages = "511-519",
doi = "10.1016/j.powtec.2016.06.028"
}

Savić, A. B., Čokeša, Đ., Lazarevic, S., Jokić, B. M., Janaćković, Đ. T., Petrović, R.,& Živković, L.. (2016). Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process. in Powder Technology, 301, 511-519.
https://doi.org/10.1016/j.powtec.2016.06.028

Savić AB, Čokeša Đ, Lazarevic S, Jokić BM, Janaćković ĐT, Petrović R, Živković L. Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process. in Powder Technology. 2016;301:511-519.
doi:10.1016/j.powtec.2016.06.028 .

Savić, Andrija B., Čokeša, Đuro, Lazarevic, Slavica, Jokić, Bojan M., Janaćković, Đorđe T., Petrović, Rada, Živković, Ljiljana, "Tailoring of magnetite powder properties for enhanced phosphate removal: Effect of PEG addition in the synthesis process" in Powder Technology, 301 (2016):511-519,
https://doi.org/10.1016/j.powtec.2016.06.028 . .

TY  - JOUR
AU  - Sremac, Snežana
AU  - Popović, Aleksandar R.
AU  - Todorović, Žaklina
AU  - Čokeša, Đuro
AU  - Onjia, Antonije E.
PY  - 2008
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3468
AB  - An interpretative strategy (factorial design experimentation + total resolution analysis + chromatogram simulation) was employed to optimize the separation of 16 polycyclic aromatic hydrocarbons (PAHs) (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo(a)anthracene, benzo(k)fluoranthene, benzo(b)fluoranthene, benzo(a)pyrene, indeno(1,2,3-c,d)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene) in temperature-programmed gas chromatography (GC). Also, the retention behavior of PAHs in the same GC system was studied by a feed-forward artificial neural network (ANN). GC separation was investigated as a function of one (linear temperature ramp) or two (linear temperature ramp+the final hold temperature) variables. The applied interpretative approach resulted in rather good agreement between the measured and the predicted retention times for PAHs in both one and two variable modeling. The ANN model, strongly affected by the number of input experiments, was shown to be less effective for one variable used, but quite successful when two input variables were used. All PAHs, including difficult to separate peak pairs (benzo(k)fluoranthene/benzo(b)fluoranthene and indeno(1,2,3-c,d)pyrene/dibenzo(a,h)anthracene), were separated in a standard (5% phenyl-95% climethylpolysiloxane) capillary column at an optimum temperature ramp of 8.0 degrees C/min and final hold temperature in the range of 260-320 degrees C. (C) 2008 Elsevier B.V. All rights reserved.
T2  - Talanta
T1  - Interpretative optimization and artificial neural network modeling of the gas chromatographic separation of polycyclic aromatic hydrocarbons
VL  - 76
IS  - 1
SP  - 66
EP  - 71
DO  - 10.1016/j.talanta.2008.02.004
ER  - 

@article{
author = "Sremac, Snežana and Popović, Aleksandar R. and Todorović, Žaklina and Čokeša, Đuro and Onjia, Antonije E.",
year = "2008",
abstract = "An interpretative strategy (factorial design experimentation + total resolution analysis + chromatogram simulation) was employed to optimize the separation of 16 polycyclic aromatic hydrocarbons (PAHs) (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo(a)anthracene, benzo(k)fluoranthene, benzo(b)fluoranthene, benzo(a)pyrene, indeno(1,2,3-c,d)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene) in temperature-programmed gas chromatography (GC). Also, the retention behavior of PAHs in the same GC system was studied by a feed-forward artificial neural network (ANN). GC separation was investigated as a function of one (linear temperature ramp) or two (linear temperature ramp+the final hold temperature) variables. The applied interpretative approach resulted in rather good agreement between the measured and the predicted retention times for PAHs in both one and two variable modeling. The ANN model, strongly affected by the number of input experiments, was shown to be less effective for one variable used, but quite successful when two input variables were used. All PAHs, including difficult to separate peak pairs (benzo(k)fluoranthene/benzo(b)fluoranthene and indeno(1,2,3-c,d)pyrene/dibenzo(a,h)anthracene), were separated in a standard (5% phenyl-95% climethylpolysiloxane) capillary column at an optimum temperature ramp of 8.0 degrees C/min and final hold temperature in the range of 260-320 degrees C. (C) 2008 Elsevier B.V. All rights reserved.",
journal = "Talanta",
title = "Interpretative optimization and artificial neural network modeling of the gas chromatographic separation of polycyclic aromatic hydrocarbons",
volume = "76",
number = "1",
pages = "66-71",
doi = "10.1016/j.talanta.2008.02.004"
}

Sremac, S., Popović, A. R., Todorović, Ž., Čokeša, Đ.,& Onjia, A. E.. (2008). Interpretative optimization and artificial neural network modeling of the gas chromatographic separation of polycyclic aromatic hydrocarbons. in Talanta, 76(1), 66-71.
https://doi.org/10.1016/j.talanta.2008.02.004

Sremac S, Popović AR, Todorović Ž, Čokeša Đ, Onjia AE. Interpretative optimization and artificial neural network modeling of the gas chromatographic separation of polycyclic aromatic hydrocarbons. in Talanta. 2008;76(1):66-71.
doi:10.1016/j.talanta.2008.02.004 .

Sremac, Snežana, Popović, Aleksandar R., Todorović, Žaklina, Čokeša, Đuro, Onjia, Antonije E., "Interpretative optimization and artificial neural network modeling of the gas chromatographic separation of polycyclic aromatic hydrocarbons" in Talanta, 76, no. 1 (2008):66-71,
https://doi.org/10.1016/j.talanta.2008.02.004 . .

TY  - JOUR
AU  - Milonjić, Slobodan K.
AU  - Čerović, Ljiljana S.
AU  - Čokeša, Đuro
AU  - Zec, Slavica
PY  - 2007
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3183
AB  - The influence of the heat treatment on the crystal structure change of five (two laboratory prepared and three commercial) silica powders were investigated. Silicas were heat treated in the temperature range from 150 to 1300 degrees C in air. Also, the influence of the washing procedure with 0.01 mol/L HCl in order to desorb cations present as impurities in silica samples, was studied. The change of the amorphous into the crystal structure (alpha-cristobalite) takes place in the range 1050-1300 degrees C, depending on the chemical purity of silica samples. Points of zero charge, pH(pzc), of the same silica samples, ranging from 3.8 to 7.1, were also determined by batch equilibration method. It is shown that the desorption of cations from silica samples, i.e., increase in their purity, leads to a shift in pH(pzc) toward lower values. (c) 2006 Elsevier Inc. All rights reserved.
T2  - Journal of Colloid and Interface Science
T1  - The influence of cationic impurities in silica on its crystallization and point of zero charge
VL  - 309
IS  - 1
SP  - 155
EP  - 159
DO  - 10.1016/j.jcis.2006.12.033
ER  - 

@article{
author = "Milonjić, Slobodan K. and Čerović, Ljiljana S. and Čokeša, Đuro and Zec, Slavica",
year = "2007",
abstract = "The influence of the heat treatment on the crystal structure change of five (two laboratory prepared and three commercial) silica powders were investigated. Silicas were heat treated in the temperature range from 150 to 1300 degrees C in air. Also, the influence of the washing procedure with 0.01 mol/L HCl in order to desorb cations present as impurities in silica samples, was studied. The change of the amorphous into the crystal structure (alpha-cristobalite) takes place in the range 1050-1300 degrees C, depending on the chemical purity of silica samples. Points of zero charge, pH(pzc), of the same silica samples, ranging from 3.8 to 7.1, were also determined by batch equilibration method. It is shown that the desorption of cations from silica samples, i.e., increase in their purity, leads to a shift in pH(pzc) toward lower values. (c) 2006 Elsevier Inc. All rights reserved.",
journal = "Journal of Colloid and Interface Science",
title = "The influence of cationic impurities in silica on its crystallization and point of zero charge",
volume = "309",
number = "1",
pages = "155-159",
doi = "10.1016/j.jcis.2006.12.033"
}

Milonjić, S. K., Čerović, L. S., Čokeša, Đ.,& Zec, S.. (2007). The influence of cationic impurities in silica on its crystallization and point of zero charge. in Journal of Colloid and Interface Science, 309(1), 155-159.
https://doi.org/10.1016/j.jcis.2006.12.033

Milonjić SK, Čerović LS, Čokeša Đ, Zec S. The influence of cationic impurities in silica on its crystallization and point of zero charge. in Journal of Colloid and Interface Science. 2007;309(1):155-159.
doi:10.1016/j.jcis.2006.12.033 .

Milonjić, Slobodan K., Čerović, Ljiljana S., Čokeša, Đuro, Zec, Slavica, "The influence of cationic impurities in silica on its crystallization and point of zero charge" in Journal of Colloid and Interface Science, 309, no. 1 (2007):155-159,
https://doi.org/10.1016/j.jcis.2006.12.033 . .

TY  - JOUR
AU  - Ražić, Slavica
AU  - Čokeša, Đuro
AU  - Sremac, Snežana
PY  - 2007
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3347
AB  - The contents of five metals (Cu, Mn, Fe, Cd, and Pb) in several red and white wines originating from different regions of Serbia were determined by name and graphite furnace atomic absorption spectrometry. The data were processed using chemometric techniques. Principal component and factor analysis were applied in order to highlight the relations between the elements and, after data reduction, three main factors controlling variability were identified. Application of hierarchical cluster analysis to the studied wines indicated differentiation of the samples belonging to different origins. No discrimination between red and white wines was found.
T2  - Journal of the Serbian Chemical Society
T1  - Multivariate data visualization methods based on elemental analysis of wines by atomic absorption spectrometry
VL  - 72
IS  - 12
SP  - 1487
EP  - 1492
DO  - 10.2298/JSC0712487R
ER  - 

@article{
author = "Ražić, Slavica and Čokeša, Đuro and Sremac, Snežana",
year = "2007",
abstract = "The contents of five metals (Cu, Mn, Fe, Cd, and Pb) in several red and white wines originating from different regions of Serbia were determined by name and graphite furnace atomic absorption spectrometry. The data were processed using chemometric techniques. Principal component and factor analysis were applied in order to highlight the relations between the elements and, after data reduction, three main factors controlling variability were identified. Application of hierarchical cluster analysis to the studied wines indicated differentiation of the samples belonging to different origins. No discrimination between red and white wines was found.",
journal = "Journal of the Serbian Chemical Society",
title = "Multivariate data visualization methods based on elemental analysis of wines by atomic absorption spectrometry",
volume = "72",
number = "12",
pages = "1487-1492",
doi = "10.2298/JSC0712487R"
}

Ražić, S., Čokeša, Đ.,& Sremac, S.. (2007). Multivariate data visualization methods based on elemental analysis of wines by atomic absorption spectrometry. in Journal of the Serbian Chemical Society, 72(12), 1487-1492.
https://doi.org/10.2298/JSC0712487R

Ražić S, Čokeša Đ, Sremac S. Multivariate data visualization methods based on elemental analysis of wines by atomic absorption spectrometry. in Journal of the Serbian Chemical Society. 2007;72(12):1487-1492.
doi:10.2298/JSC0712487R .

Ražić, Slavica, Čokeša, Đuro, Sremac, Snežana, "Multivariate data visualization methods based on elemental analysis of wines by atomic absorption spectrometry" in Journal of the Serbian Chemical Society, 72, no. 12 (2007):1487-1492,
https://doi.org/10.2298/JSC0712487R . .

TY  - JOUR
AU  - Vasiljevic, T
AU  - Onjia, Antonije E.
AU  - Čokeša, Đuro
AU  - Laušević, Mila D.
PY  - 2004
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2812
AB  - An artificial neural network (ANN) model for the prediction of retention times in high-performance liquid chromatography (HPLC) was developed and optimized. A three-layer feed-forward ANN has been used to model retention behavior of nine phenols as a function of mobile phase composition (methanol-acetic acid mobile phase). The number of hidden layer nodes, number of iteration steps and the number of experimental data points used for training set were optimized. By using a relatively small amount of experimental data (25 experimental data points in the training set), a very accurate prediction of the retention (percentage normalized differences between the predicted and the experimental data less than 0.6%) was obtained. It was shown that the prediction ability of ANN model linearly decreased with the reduction of number of experiments for the training data set. The results obtained demonstrate that ANN offers a straightforward way for retention modeling in isocratic HPLC separation of a complex mixture of compounds widely different in pK(a) and log K-ow values. (C) 2004 Elsevier B.V. All rights reserved.
T2  - Talanta
T1  - Optimization of artificial neural network for retention modeling in high-performance liquid chromatography
VL  - 64
IS  - 3
SP  - 785
EP  - 790
DO  - 10.1016/j.talanta.2004.03.032
ER  - 

@article{
author = "Vasiljevic, T and Onjia, Antonije E. and Čokeša, Đuro and Laušević, Mila D.",
year = "2004",
abstract = "An artificial neural network (ANN) model for the prediction of retention times in high-performance liquid chromatography (HPLC) was developed and optimized. A three-layer feed-forward ANN has been used to model retention behavior of nine phenols as a function of mobile phase composition (methanol-acetic acid mobile phase). The number of hidden layer nodes, number of iteration steps and the number of experimental data points used for training set were optimized. By using a relatively small amount of experimental data (25 experimental data points in the training set), a very accurate prediction of the retention (percentage normalized differences between the predicted and the experimental data less than 0.6%) was obtained. It was shown that the prediction ability of ANN model linearly decreased with the reduction of number of experiments for the training data set. The results obtained demonstrate that ANN offers a straightforward way for retention modeling in isocratic HPLC separation of a complex mixture of compounds widely different in pK(a) and log K-ow values. (C) 2004 Elsevier B.V. All rights reserved.",
journal = "Talanta",
title = "Optimization of artificial neural network for retention modeling in high-performance liquid chromatography",
volume = "64",
number = "3",
pages = "785-790",
doi = "10.1016/j.talanta.2004.03.032"
}

Vasiljevic, T., Onjia, A. E., Čokeša, Đ.,& Laušević, M. D.. (2004). Optimization of artificial neural network for retention modeling in high-performance liquid chromatography. in Talanta, 64(3), 785-790.
https://doi.org/10.1016/j.talanta.2004.03.032

Vasiljevic T, Onjia AE, Čokeša Đ, Laušević MD. Optimization of artificial neural network for retention modeling in high-performance liquid chromatography. in Talanta. 2004;64(3):785-790.
doi:10.1016/j.talanta.2004.03.032 .

Vasiljevic, T, Onjia, Antonije E., Čokeša, Đuro, Laušević, Mila D., "Optimization of artificial neural network for retention modeling in high-performance liquid chromatography" in Talanta, 64, no. 3 (2004):785-790,
https://doi.org/10.1016/j.talanta.2004.03.032 . .

TY  - JOUR
AU  - Onjia, Antonije E.
AU  - Milonjić, Slobodan K.
AU  - Čokeša, Đuro
AU  - Čomor, Mirjana
AU  - Miljević, Nada R.
PY  - 2003
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2660
AB  - Colloidal particles of chromia have been prepared by forced hydrolysis of an aqueous solution containing chromium chloride hexahydrate. At elevated temperature, a controlled addition of potassium hydroxide yielded colloidal chromia particles. After the sol coagulation, amorphous dried residues (I) were converted to crystalline form (II) by heating at 1073 K. The thermal treatment was also accompanied by a reduction in both surface area (from 75 to 9 m(2)/g) and point of zero charge (pH(pzc); from 4.7 to 4.0). Chromia dissolution over the studied pH range (pH = 2-12) exhibits a parabolic trend, with minimum solubility at pH(pzc). (C) 2003 Elsevier Ltd. All rights reserved.
T2  - Materials Research Bulletin
T1  - Characterization of colloidal chromia particles obtained by forced hydrolysis
VL  - 38
IS  - 8
SP  - 1329
EP  - 1339
DO  - 10.1016/S0025-5408(03)00137-5
ER  - 

@article{
author = "Onjia, Antonije E. and Milonjić, Slobodan K. and Čokeša, Đuro and Čomor, Mirjana and Miljević, Nada R.",
year = "2003",
abstract = "Colloidal particles of chromia have been prepared by forced hydrolysis of an aqueous solution containing chromium chloride hexahydrate. At elevated temperature, a controlled addition of potassium hydroxide yielded colloidal chromia particles. After the sol coagulation, amorphous dried residues (I) were converted to crystalline form (II) by heating at 1073 K. The thermal treatment was also accompanied by a reduction in both surface area (from 75 to 9 m(2)/g) and point of zero charge (pH(pzc); from 4.7 to 4.0). Chromia dissolution over the studied pH range (pH = 2-12) exhibits a parabolic trend, with minimum solubility at pH(pzc). (C) 2003 Elsevier Ltd. All rights reserved.",
journal = "Materials Research Bulletin",
title = "Characterization of colloidal chromia particles obtained by forced hydrolysis",
volume = "38",
number = "8",
pages = "1329-1339",
doi = "10.1016/S0025-5408(03)00137-5"
}

Onjia, A. E., Milonjić, S. K., Čokeša, Đ., Čomor, M.,& Miljević, N. R.. (2003). Characterization of colloidal chromia particles obtained by forced hydrolysis. in Materials Research Bulletin, 38(8), 1329-1339.
https://doi.org/10.1016/S0025-5408(03)00137-5

Onjia AE, Milonjić SK, Čokeša Đ, Čomor M, Miljević NR. Characterization of colloidal chromia particles obtained by forced hydrolysis. in Materials Research Bulletin. 2003;38(8):1329-1339.
doi:10.1016/S0025-5408(03)00137-5 .

Onjia, Antonije E., Milonjić, Slobodan K., Čokeša, Đuro, Čomor, Mirjana, Miljević, Nada R., "Characterization of colloidal chromia particles obtained by forced hydrolysis" in Materials Research Bulletin, 38, no. 8 (2003):1329-1339,
https://doi.org/10.1016/S0025-5408(03)00137-5 . .

TY  - JOUR
AU  - Onjia, Antonije E.
AU  - Vasiljevic, T
AU  - Čokeša, Đuro
AU  - Laušević, Mila D.
PY  - 2002
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/2593
AB  - A multifactor optimization strategy was utilized to predict the isocratic HPLC separation of nine phenols. The retention behavior was studied as a function of changing eluent (methanol - acetic acid) composition. The predicted and measured retentions; are in rather good agreement. To locate the optimum in the factor space, the normalized resolution product criterion was applied. In virtually every case, the resolution is limited by the separation of the 2-chlorophenol and 2,4-dinitrophenol pair.
T2  - Journal of the Serbian Chemical Society
T1  - Factorial design in isocratic high-performance liquid chromatography of phenolic compounds
VL  - 67
IS  - 11
SP  - 745
EP  - 751
DO  - 10.2298/JSC0211745O
ER  - 

@article{
author = "Onjia, Antonije E. and Vasiljevic, T and Čokeša, Đuro and Laušević, Mila D.",
year = "2002",
abstract = "A multifactor optimization strategy was utilized to predict the isocratic HPLC separation of nine phenols. The retention behavior was studied as a function of changing eluent (methanol - acetic acid) composition. The predicted and measured retentions; are in rather good agreement. To locate the optimum in the factor space, the normalized resolution product criterion was applied. In virtually every case, the resolution is limited by the separation of the 2-chlorophenol and 2,4-dinitrophenol pair.",
journal = "Journal of the Serbian Chemical Society",
title = "Factorial design in isocratic high-performance liquid chromatography of phenolic compounds",
volume = "67",
number = "11",
pages = "745-751",
doi = "10.2298/JSC0211745O"
}

Onjia, A. E., Vasiljevic, T., Čokeša, Đ.,& Laušević, M. D.. (2002). Factorial design in isocratic high-performance liquid chromatography of phenolic compounds. in Journal of the Serbian Chemical Society, 67(11), 745-751.
https://doi.org/10.2298/JSC0211745O

Onjia AE, Vasiljevic T, Čokeša Đ, Laušević MD. Factorial design in isocratic high-performance liquid chromatography of phenolic compounds. in Journal of the Serbian Chemical Society. 2002;67(11):745-751.
doi:10.2298/JSC0211745O .

Onjia, Antonije E., Vasiljevic, T, Čokeša, Đuro, Laušević, Mila D., "Factorial design in isocratic high-performance liquid chromatography of phenolic compounds" in Journal of the Serbian Chemical Society, 67, no. 11 (2002):745-751,
https://doi.org/10.2298/JSC0211745O . .