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454 items
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Heavy metals and trace element accumulation and distribution in the organs of Phragmites australis (Cav.) Trin. eh Steud. 1841, Tisza River, Srebia
Štrbac Snežana, Jovančićević Branimir, Šajnović Aleksandra, Simonović Predrag, Dojčinović B., Grubin Kašanin Milica, Vasić Nebojša, Srdić D. (2012)Štrbac Snežana, Jovančićević Branimir, Šajnović Aleksandra, Simonović Predrag, Dojčinović B., Grubin Kašanin Milica, Vasić Nebojša, Srdić D.. "Heavy metals and trace element accumulation and distribution in the organs of Phragmites australis (Cav.) Trin. eh Steud. 1841, Tisza River, Srebia" in 9th International Symposium on Environmental Geochemistry, Aveiro, Portugal: (2012): 322-322
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Crystal structure of (Bi0.94Sb1.06)S3 and reconsideration of cation distribution over mixed sites in the bismuthinite-stibnite solid-solution series
Poleti Dejan, Karanović Ljiljana, Balić Žunić Tonči, Gržetić Ivan. "Crystal structure of (Bi0.94Sb1.06)S3 and reconsideration of cation distribution over mixed sites in the bismuthinite-stibnite solid-solution series" in Neues Jahrbuch für Mineralogie - Abhandlungen 189 no. 2, Johannesstr. 3A D-70176 Stuttgart, Germany: E. Schweizerbarsche Verlagsbuchhandlung (2012): 177-187. https://doi.org/10.1127/0077-7757/2012/0217
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Effectiveness Analysis of Different Bucket-wheel Excavators
Coal production in open-pit lignite mines in the Republic of Serbia is performed with continuous work systems. In addition to coal production, the same systems are used for the exploitation of large quantities of overburden. According to the reliability concept, continuous systems are in linear connection. If the failure occurs in one part of the system, that will produce a downtime of the entire system. The initial and most important factor of continuous systems is the bucket-wheel excavator. It ...Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić. "Effectiveness Analysis of Different Bucket-wheel Excavators" in 8th International Conference Mining and Environmental Protection, Sokobanja, 22-25 September 2021, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2021)
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Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention
Gas wells, particularly those situated onshore, play a vital role in the global energy sector by supplying a significant portion of natural gas. However, operational challenges, notably gas hydrate formation, pose substantial issues, leading to complications such as flowline blockages and unexpected well shutdowns. Gas hydrates, crystalline structures resembling ice, ...Gas Well, Gas Hydrate Formation, Well Modeling, Well Performance Optimization, Choke Position Adjustments, Methanol InjectionMilica Ješić, Bojan Martinović, Stefan Stančić, Miroslav Crnogorac, Dušan Danilović. "Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention" in Underground Mining Engineering, Beograd : Rudarsko-geološki fakultet (2023)
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Sinteza i karakterizacija nanoprahova u CeO2-Bi2O3 sistemu
Marija D. Prekajski (2014-04-04)Nanoprahovi kristalnih faza iz serije čvrstih rastvora u pseudo-binarnom sistemuCeO2-Bi2O3 sintetisani su primenom jednostavne i ekonomične samopropagirajućemetode na sobnoj temperaturi korišćenjem nitrata metala i natrijum-hidroksida kaopolaznih supstanci. Osim krajnjih članova niza, CeO2 i niskotemperaturne polimorfnemodifikacije α-Bi2O3, sintetisani su i čvrsti rastvori nominalnog sastava Ce1-xBixO2-δ,gde je x = 0,1; 0,2; 0,3; 0,4; 0,5; 0,6; 0,7; 0,8; 0,9. Rezultati proučavanja metodomrendgenske difraktometrije na polikristalnom materijalu i ramanske spektroskopskeanalize pokazali su da su sintetisani prahovi sa nižim sadržajem bizmuta (x = 0,1 ...nanostrukturni materijali, čvrsti rastvori, CeO2, Bi2O3, rendgenskadifraktometrija praha, Ritveldova metoda, mikrostrukrurna analizaMarija D. Prekajski. "Sinteza i karakterizacija nanoprahova u CeO2-Bi2O3 sistemu" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2014-04-04)
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Temperature induced evolution of nanostructured Ni0.9Zn0.1O
Kremenović Aleksandar, Antić Bratislav, Vučinić-Vasić Milica, Colomban Philippe, Jovalekić Čedomir, Bibić Nataša, Kahlenberg Volker, Leoni Matteo (2010)The crystal structure and microstructure of as-prepared and annealed Ni0.9Zn0.1O were refined at room temperature in both the Fm (3) over barm and R (3) over barm space groups. It is shown that below the Neel point (458 K), where magnetic ordering triggers the presence of a trigonal strain, the common usage of a higher-symmetry non-admissible space group for crystal structure and microstructure analysis via the Rietveld method may result in both an incorrect structure description and incorrect microstructure ...Kremenović Aleksandar, Antić Bratislav, Vučinić-Vasić Milica, Colomban Philippe, Jovalekić Čedomir, Bibić Nataša, Kahlenberg Volker, Leoni Matteo. "Temperature induced evolution of nanostructured Ni0.9Zn0.1O" in Journal of Applied Crystallography no. 43, Denmark: Blackwell Munksgaard (2010). https://doi.org/10.1107/S0021889810019163
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Surface functional groups and degree of carbonization of selected chars from different processes and feedstock
Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann (2022)The knowledge ofthe structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness ...Biougalj, različiti procesi dobijanja, različite sirovine, površinski aktivne grupe, x-ray, FT-IR,XPS... Schlitt GmbH (Antrifttal-Ohmes, Germany) using HTC at 200 'C for typically 4-8 h. Other materials. Sand F36 with 97% of the material having a grain size between 125— 250 Hm was obtained from Quarzwerke Hurth. All chemicals including NaCI, KBr, Na,H- POu·12H5O, NaOH, HCI used in this work were ...
... terraces. The size of the larger particles of AC2 (Fig 1a) corre- sponds to the size given by the provider (36–150 um), but smaller particles are also visible. Sla Fig in S1 File shows the image of AC1 with a larger amount of smaller particles in accordance with the particle size (75% < 40 um) ...
... crystal of extended (infinite) size [104]. Polycrystalline graphite exhibits a second peak at 1355 cm” that is assigned to the Ay, mode, which becomes Raman active for finite crystal size [104]. The intensity of that peak and the peak position are related to the crystal size [104] and depend on the ...Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann. "Surface functional groups and degree of carbonization of selected chars from different processes and feedstock" in PLOS ONE (2022). https://doi.org/10.1371/journal.pone.0277365
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Atmospheric exposure vs burying: influences on damage intensity of built-in kersantite in the monument of the Small Staircase (Belgrade, Serbia)
Proučavan je efekat „zatrpanog kamena“ na intenzitet procesa degradacije prisutnih na kersantitu koji je ugrađen u spomenik Malo stepenište. Istraživanja su vršena na uzorcima stene iz kamenoloma i na oštećenim kamenim blokovima ugrađenim u spomenik. Dok su neki delovi stepeništa bili pod zemljom 90 godina, većina kamenih elemenata je bila izložena različitim uslovima sredine i antropogenim uticajima. Urađeno je detaljno mapiranje trenutnog stanja spomenika kako bi se istražio uticaj “zatrpavanja” i kompleksne geometrije spomenika na tip propadanja i variranje ...Nevenka Novaković, Predrag Dabić, Vesna Matović. "Atmospheric exposure vs burying: influences on damage intensity of built-in kersantite in the monument of the Small Staircase (Belgrade, Serbia)" in Environmental Earth Sciences, Springer Science and Business Media LLC (2023). https://doi.org/10.1007/s12665-023-10794-6
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Density maps from gravity inversion as a tool for the basin basement analysis and imaging
Ivana Vasiljević (2023)Previously devised method for density mapping of the Cenozoic basin’s basement is further developed in order to improve the visualization and geological interpretation of the results. The method combines gravity-density inversion with forward modeling and requires gravity anomaly and depth-to-basement data. Although it was primarily designed for application in well-researched basins, such as Pannonian basin, method does not require further constrains. An information on density distribution in the Cenozoic sediments (from density logging or core density measurements) is important ...Ivana Vasiljević. "Density maps from gravity inversion as a tool for the basin basement analysis and imaging" in GEOSCIENCE 2023, Bucharest, Romania, November 9-11, 2023., Bucharest : SGAR - Romanian Society of Applied Geophysics (2023)
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Spatial distribution of major and trace elements in artificial lakes in Serbia: health risk indices and suitability of water for drinking and irrigation purposes
Goran Marković, Aleksandar Ž. Kostić, Nebojša Đ. Pantelić, Radojka Maletić, Jana Štrbački, Jovan Cakić, Lazar Kaluđerović, Biljana P. Dojčinović, Angelo Maria Giuffrè, Jelena B. Popović-Djordjević (2023)Lakes and reservoirs are the main water resources for household, irrigation, and industrial use. Hence, it is necessary to control water pollution and have reliable information on water quality, which refers to its suitability for a particular purpose. The main objective of this study was to evaluate the suitability of water for drinking and irrigation purposes from ten artificial lakes on the territory of the Republic of Serbia. The physicochemical parameters were determined using standard analytical methods, whereas the ...Goran Marković, Aleksandar Ž. Kostić, Nebojša Đ. Pantelić, Radojka Maletić, Jana Štrbački, Jovan Cakić, Lazar Kaluđerović, Biljana P. Dojčinović, Angelo Maria Giuffrè, Jelena B. Popović-Djordjević. "Spatial distribution of major and trace elements in artificial lakes in Serbia: health risk indices and suitability of water for drinking and irrigation purposes" in Environmental Monitoring and Assessment, Springer Science and Business Media LLC (2023). https://doi.org/10.1007/s10661-023-11740-6
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Distribution of Uranium and Rare Elements in Radioactive Phosphate-Bearing Anomalies in Southeast Mongolia
Boris Vakanjac, Neil Rutherford, Vesna Ristić Vakanjac, Tanita Đumić, Suzana Đorđević Milošević (2020)Soviet and Mongolian geologists initiated geological exploration of Mongolia for minerals after World War II (1945). These activities lasted until the breakup of the USSR in 1991. As part of this exploration systematic uranium and rare element exploration was undertaken across Mongolia. New exploration resumed in Mongolia at the beginning of the 21st century for a range of ore and mineral deposit styles including uranium, coal, base and precious metals and Fe-ore. This was generally undertaken by Western-based companies. This ...Boris Vakanjac, Neil Rutherford, Vesna Ristić Vakanjac, Tanita Đumić, Suzana Đorđević Milošević. "Distribution of Uranium and Rare Elements in Radioactive Phosphate-Bearing Anomalies in Southeast Mongolia" in Minerals, MDPI AG (2020). https://doi.org/10.3390/min10040307
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Heavy metals in lignite and soil of Kostolac-Kovin coal basin, eastern Serbia - comparative analysis with selected cities in Serbia, region, Europe and world
Bogoljub Vučković, Bojan Dimitrijević (2023)The Kostolac-Kovin coal basin with an area of 320 km2, with 5 separate layers of coal and with a total of about 5.7 Bt of geological resources and reserves represents an exceptional potential for coal production in Serbia. The coal resources listed in this way are not fully exploitable, but they represent potential for consideration. In this paper, we deal with the geochemical characteristics of coal seams and perform a comparative analysis of coal affectation on the environment. With ...... ıdcocrsayoocrszloop?aziO Figure 4. General view of the horizontal distribution of Zn, Cu and Pb in the I, I and II coal seams of the Kostolac- Kovin coal-bearing basin; blue — increased values, yellow — decreased values VERTICAL DISTRIBUTION A large number of individual samples were taken in the vertical ...
... including the surface humus layer, gravel, coal layers and all types of clay and sand. A presentation of the vertical distribution of Zn, Pb, Cu is given (Figure 5). 180 Vertical distribution Zn (ppm) Surface soil, humus BHWIIAGIGII II Q3 Quaternarygravel E 47 Quaternaryclays 00008 322 Quaternarysands ...
... environment. P/ith 155 analyzes of HM from coal, 45 from ash, 165 from gravel and 30 from soil, we perform analysis of horizontal and vertical distribution of HM and comparative analysis. B/hat interests us as authors and you as readers the most is - whether heavy metals from coal contaminate the ...Bogoljub Vučković, Bojan Dimitrijević. "Heavy metals in lignite and soil of Kostolac-Kovin coal basin, eastern Serbia - comparative analysis with selected cities in Serbia, region, Europe and world" in 9th International Conference Mining and Environmental Protection, 24–27. May 2023, Sokobanja, Beograd : Univerzitet u Beogradu, Rudarsko-geološki fakultet (2023)
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A comparative study of the molecular and isotopic composition of biomarkers in immature oil shale (Aleksinac deposit, Serbia) and its liquid pyrolysis products (open and closed systems)
Gordana Gajica, Aleksandra Šajnović, Ksenija Stojanović, Jan Schwarzbauer, Aleksandar Kostić, Branimir Jovančićević (2021)The molecular and isotopic composition of biomarkers in initial bitumen isolated from immature (0.41% Rr) oil shale samples (Aleksinac deposit) and liquid products obtained by pyrolysis in open (OS) and closed (CS) systems are studied. The influence of pyrolysis type and variations of kerogen type on biomarkers composition and their isotopic signatures in liquid products is determined. The applicability of pyrolysis type, numerous biomarkers and carbon isotopic compositions (δ13C) of n-alkanes in liquid pyrolysates is established. Pyrolysis experiments were ...Uljni šejl, Aleksinac, organska supstanca, otvoreni i zatvoreni sistem pirolize, biomarkeri, izotopski sastav ugljjenikaGordana Gajica, Aleksandra Šajnović, Ksenija Stojanović, Jan Schwarzbauer, Aleksandar Kostić, Branimir Jovančićević. "A comparative study of the molecular and isotopic composition of biomarkers in immature oil shale (Aleksinac deposit, Serbia) and its liquid pyrolysis products (open and closed systems)" in Marine and Petroleum Geology, Elsevier BV (2021). https://doi.org/10.1016/j.marpetgeo.2021.105383
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Distribution of Potentially Toxic Elements in the City of Zintan and Its Surroundings (Northwestern Libya) by Surface Soil Sampling
Boris Vakanjac, Zorana Naunović, Vesna Ristić Vakanjac, Tanita Đumić, Saša Bakrač, Jana Štrbački, Vuk Gajić, Taher Mohamed Alzarog (2023)The study area is the city of Zintan, in northwestern Libya, which has grown over the past 30 years. Its current population is roughly 30,000. Although the city is in part commercial, most of the population engages in agriculture and primarily grows cereal crops (wheat and barley). The demand of the growing city for agricultural products has increased, intensifying the use of fertilizers, pesticides, and insecticides. Consequently, concentrations of potentially toxic elements (PTE) in the soil have increased. To ...Boris Vakanjac, Zorana Naunović, Vesna Ristić Vakanjac, Tanita Đumić, Saša Bakrač, Jana Štrbački, Vuk Gajić, Taher Mohamed Alzarog. "Distribution of Potentially Toxic Elements in the City of Zintan and Its Surroundings (Northwestern Libya) by Surface Soil Sampling" in Minerals, MDPI AG (2023). https://doi.org/10.3390/min13081048
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Micro- to nanoscale textures of gold in arsenopyrite and scorodite from the As-Au-Bi assemblage of Drenjak locality (Serbia)
Ivana Jelić, Janez Zavašnik, Marina Lazarov, Alena Zdravković, Sabina Kovač, Jovica Stojanović, Aleksandar Pačevski (2023)Arsenopyrite and pyrite are important carriers of Au that is present in the form of microscopic and “invisible” gold. Such gold can be expected to be released upon the process of oxidation of these sulfides. In studied gold mineralization at Drenjak, related to the granitoids of the Oligocene-Miocene Kopaonik Ore District, the main arsenopyrite-pyrite-(bismuthinite) sulfide assemblage was formed in the quartz bodies and partly replaced by scorodite (FeAsO4·2H2O) and Bi-arsenate. With only up to 5 ppm of gold recorded ...Ivana Jelić, Janez Zavašnik, Marina Lazarov, Alena Zdravković, Sabina Kovač, Jovica Stojanović, Aleksandar Pačevski. "Micro- to nanoscale textures of gold in arsenopyrite and scorodite from the As-Au-Bi assemblage of Drenjak locality (Serbia)" in Ore Geology Reviews, Elsevier BV (2023). https://doi.org/10.1016/j.oregeorev.2023.105711
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The use of biological markers in determination of origin and type of organic matter in the Tisza river sediments
Snežana Štrbac, Gordana Gajica, Aleksandra Šajnović, Nebojša Vasić, Ksenija Stojanović, Branimir Jovančićević (2013)The objective of the study was to determine the origin and type of organic matter (OM) of the Tisza recent sediments along the distance of 153 km through the territory of Serbia. For this purpose group organic-geochemical parameters and biomarker compositions were used. All samples contain approximately same amount of OM, which was deposited under uniform, slightly reducing conditions. Based on the distribution of n-alkanes, the origin and type of OM could not be precisely estimated. However, n-alkane patterns ...... origin. This primarily refers to n-alkanes. In crude oils, n-alkanes have uniform distribution of odd and even homologues (the Carbon Preference Index, CPI, is about 1), usually in the range of C10–C35. An n-alkane distribution with a strong predominance of lower homologues C12–C22 indicates algal organic ...
... Preference Index (CPI) determined for the full distribution of n-alkanes C16–C35 (mass chromatogram m/z 71), CPI (C16–C35) = 1/2 [Σodd(n-C17–n-C35) / Σeven(n-C16–n-C34) + Σodd(n-C17–n-C35) / Σeven(n-C18–n- –C36)]; bCPI determined for the distribution of n-alkanes C16–C22 (mass chromatogram m/z 71) ...
... 2)]; cCPI deter- mined for distribution of n-alkanes C23–C35 (mass chromatogram m/z 71), CPI (C23–C35) = 1/2 [Σodd(n-C23– –n-C35) / Σeven(n-C22–n-C34)+Σodd(n-C23–n-C35) / Σeven(n-C24–n-C36)]; dPr/Ph = pristane/phytane Tricyclic and pentacyclic terpanes. The distribution of tricyclic diterpanes and ...Snežana Štrbac, Gordana Gajica, Aleksandra Šajnović, Nebojša Vasić, Ksenija Stojanović, Branimir Jovančićević. "The use of biological markers in determination of origin and type of organic matter in the Tisza river sediments" in Journal of Serbian Chemical Society, Beograd : Srpsko hemijsko društvo (2013). https://doi.org/10.2298/JSC130614087S
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Gas-lift wells optimization at the oil field "K"
Dušan Danilović, Marija Ilić, Miroslav Crnogorac, Lola Tomić. "Gas-lift wells optimization at the oil field "K"" in Podzemni radovi, University of Belgrade - Faculty of Mining and Geology (2022). https://doi.org/10.5937/podrad2241031D
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3D modeling and monitoring of karst system as a base for its evaluation and utilization: a case study from eastern Serbia
Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeSaša Milanović, Zoran Stevanović, Ljiljana Vasić, Vesna Ristić-Vakanjac. "3D modeling and monitoring of karst system as a base for its evaluation and utilization: a case study from eastern Serbia" in Environmental Earth Sciences, Springer Science and Business Media LLC (2013). https://doi.org/10.1007/s12665-013-2591-9
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Some examples of interactions between certain rare earth elements and soil
... radiation from the copper (Cu) anticathode, Wavelength, nm 15.4178 Scan range, 2 o 2 – 70 Step size, 2 o 0.01 Time constant, o / min 10 Scan range (clay minerals), 2 o 2 – 30 Step size (clay minerals), 2 o 0.01 Time constant (clay minerals), o / min 5 Acce pted M anuscr ipt ...
... adjusted. The solutions were mixed at the shaker at the speed of 80 rpm for two hours, and then they were filtered through “blue band” filter paper (pores size < 2 μm) into the 100 mL volumetric flasks. The sediments were rinsed three times with 10 mL distilled water each and filled up with distilled water ...
... INTERACTIONS OF RARE EARTH ELEMENTS AND SOIL 5 quantity of adsorbate remaining in the equilibrium solution following adsorption, whereby the distribution between the liquid and solid phase of adsorption solution for different concentrations is presented. Most often by adsorption isotherms the i ...Zlatko Nikolovski, Jelena Isailović, Dejan Jeremić, Sabina Kovač, Ilija Brčeski. "Some examples of interactions between certain rare earth elements and soil" in Journal of the Serbian Chemical Society, National Library of Serbia (2021). https://doi.org/10.2298/JSC211006095N
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Uniaxial compressive strength test before and after standard fire test on rock mass
Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović (2022)... INTRODUCTION Uniaxial compressive strength testing is a parameter that is determined experimentally. It depends on the structure of the rock mass, grain size and orientation, number and arrangement of cracks and fissures. For the same rock, strength may be different, depending on physical characteristics ...
... of this mineral during transport. The rock fragments are rounded, sometimes jagged, up to 0.1 mm in size. There are also fragments of carbonate rocks, which do not differ from other grains in size and shape. The mentioned diversity indicates a wider area of erosion from different types of rocks ...
... . Some have undulatory extincion due to the effect of pressure, which tells us that they are at least partly of metamorphic origin. The different size of this mineral, poorly sorted indicates a relatively short transport of the material. Crystal fragments are less presented, mostly small and ...Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović. "Uniaxial compressive strength test before and after standard fire test on rock mass" in Fifth symposium of the Macedonian Association for Geotechnics, Ohrid, North Macedonia, 23-25. 06. 2022, Macedonian Association for Geotechnics (2022)