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2368 items
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Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides
... occurs on the high-energy sorption centers at lower pesticide concentrations (specific adsorption), and low-energy sorption centers at higher pesticide concentrations (non-specific adsorption). In the case of montmorillonites modified both by the HDTMA and PTMA complexes, ...
... Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Call for contributions Clean water and sanitation & Life on land Linking soil mineralogy to soil properties and functions ...
... Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides Lazar Kaluđerović, Zorica Tomić, Rada Đurović-Pejčev, Maja Milošević Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization ...Lazar Kaluđerović, Zorica Tomić, Rada Đurović-Pejčev, Maja Milošević. "Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides" in Eurosoil2020, online event 2021, Eurosoil, Frontiers Abstract Book (2021)
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Photocatalytic Activity of the V2O5 Catalyst toward Selected Pharmaceuticals and Their Mixture: Influence of the Molecular Structure on the Efficiency of the Process
Sanja J. Armaković, Aleksandra Jovanoski Kostić, Andrijana Bilić, Maria M. Savanović, Nataša Tomić, Aleksandar Kremenović, Maja Šćepanović, Mirjana Grujić-Brojčin, Jovana Ćirković, Stevan Armaković (2023)Due to the inability of conventional wastewater treatment procedures to remove organic pharmaceutical pollutants, active pharmaceutical components remain in wastewater and even reach tap water. In terms of pharmaceutical pollutants, the scientific community focuses on -blockers due to their extensive (over)usage and moderately high solubility. In this study, the photocatalytic activity of V2O5 was investigated through the degradation of nadolol (NAD), pindolol (PIN), metoprolol (MET), and their mixture under ultraviolet (UV) irradiation in water. For the preparation of V2O5, facile ...DFT analysis, metoprolol, nadolol, nanomaterial characterization, photocatalysis, pindolol, β-blocker... Figure 6. Transformed Kubelka-Munk functions (F(R) hv)Ž and (F(R) hv)1/? assuming,direct and indirect energy bandgap in the V»Os sample, respectively. It should be noted that different V)»Os structures may undergo direct and indirect transitions, and it is not often easy to decide which type of electron ...
... (MET, NAD, and PIN) separately and in a mixture. Several methods of characterization, such as X-ray powder diffraction (KRPD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET) measurements, Fourier transform infrared (FTIR) and Raman sp ...
... A—proportional con- stant, and the n factor depends on the nature of the electron transition. They equal 1/2 or 2 for allowed direct and indirect transition band gaps [36]. The band gap values were deduced by extrapolating the linear portion of the curves to the energy axis, as shown in Figure ...Sanja J. Armaković, Aleksandra Jovanoski Kostić, Andrijana Bilić, Maria M. Savanović, Nataša Tomić, Aleksandar Kremenović, Maja Šćepanović, Mirjana Grujić-Brojčin, Jovana Ćirković, Stevan Armaković. "Photocatalytic Activity of the V2O5 Catalyst toward Selected Pharmaceuticals and Their Mixture: Influence of the Molecular Structure on the Efficiency of the Process" in Molecules, MDPI AG (2023). https://doi.org/10.3390/molecules28020655
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Design of a sucker rod pumping system
Ana Ponoćko (2024)For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...... round cross-section and are used to transmit energy from the surface equipment (horsehead) to the downhole pump. Their lengths range from 7.62 meters to 9.1 meters and feature reinforced male threads and a square section for gripping with wrenches during installation and removal [3.,8]. The ...
... ofthe surface and pump dynamometer card and plot the net gear box torque over a stroke. To arrive at the final form of the wave equation, it is necessary to consider and determine the "damping force." Due to the pumping cycle, there is a continuous and irreversible loss of energy caused by the ...
... fluid to move from the reservoir into the well and then through the production system. If the production of fluid relies solely on the natural energy of the reservoir, this method of exploitation is called an eruptive method. When the reservoir energy is sufficiently depleted, so that the reservoir ...Ana Ponoćko. Design of a sucker rod pumping system, 2024
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Application of machine learning for diagnosing the operation of a deep well pump in oil production
Maja Trikić (2024)This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost... operation Frequent changes in pump operation and fluid composition lead to variations in the load and energy consumption of the system. Based on the physical characteristics of the well and measured values of load and smooth rod stroke, theoretical and surface dynamograms are generated. Mathematical ...
... for applications involving liquids and gases, such as in water management systems and industrial processes. 34 ' ··o Serija Q45U Serija 518 RUC30/100/300/600 M2SU Figure5.5 Ultrasonic sensors 3.Electromagnetic sensors- These sensors use Faraday's law of electromagnetic induction to measure ...
... difference between the discharge and suction pressures represents the pumping pressure, which is an indicator of the increase in potential energy of the fluid. The efficiency of the pump depends on its ability to convert mechanical energy into the potential energy of the fluid. Free gas in the fluid ...Maja Trikić. Application of machine learning for diagnosing the operation of a deep well pump in oil production, 2024
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Mine surveying works for the purpose of excavating the remaining reserves of bauxite in the deposit of “Podbracan”
... direction angles σβ = ± 20ʺ and stan- dard deviation for setting out length σ d = ± 0.01m were adopted. Based on the standard deviations for given dimensions and adopted standard deviations of dimensions to be set out, and in accordance with (1), by implementing the General Law on the Propagation ...
... 15" was adopted, as well as standard deviations for measuring the instrument height and the altitude of signal of σ i = σ l = ± 0.01m. In accordance with (8), and by implementing the General Law on Propagation of Variances (Wolf & Ghilani, 1997), standard deviations for elevation differences ...
... are vastly spread both horizontally and vertically (approximately 300m in thickness) and discordantly lies over the older beds. They are consisted of sandy and grav- elly clays, clayly and ironaceus quartz sands and semi-consolidated sand- stones, laterally and vertically shifting on the bauxite ...Aleksandar Milutinović, Aleksandar Ganić, Thamer Rayes Diyab, Rade Tokalić, Meri Ganić. "Mine surveying works for the purpose of excavating the remaining reserves of bauxite in the deposit of “Podbracan”" in Revista Escola de Minas, School of Mines Magazine, Sao paulo, Brasil : SciELO (2015)
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Economic And Technical Aspects Of Transformer Operation
Aleksandrović Snežana, Jović Mihajlo (2016)Aleksandrović Snežana, Jović Mihajlo. "Economic And Technical Aspects Of Transformer Operation" in Energy Sources, Part B: Economics, Planning and Policy 11 no. 1, United Kingdom:Taylor & Francis (2016): 26-31. https://doi.org/10.1080/15567249.2011.567225
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Mineral safeguarding in Serbia
Vladimir Simić, Dragana Životić, Zoran Miladinović. "Mineral safeguarding in Serbia" in Mineral deposits safeguarding as a basis of mineral raw materials safety, 10–11 May 2022 Kraków, Poland, Publishing House MEERI PAS (2022)
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Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit
... potential energy of explosive transformes into mechanical work. In the near of the blasting point, that energy destroys and crushes the rock mass. At a slightly greater distance that energy creates cracks and permanent deformations in the rock mass while at an even greater distance that energy transformes ...
... of kilograms per a drillhol and blasting with dozens and even hundreds of tonnes of an explosive are being apllied in the world nowdays. Such large quantities of an explosive can cause seismic shocks with the intensity that can have hazardous impact on the environment and result in moving of buildings ...
... monitoring site r , reduced to the total quantity of the explosive Q i.e., R =%č. Parameters K and m are conditioned by } v characteristics of the rock mass and blasting conditions. Thus, V is a decreasing and convex function of the variable R. By applying the equation of rock mass oscillation while ...Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac. "Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit" in 9th International Conference Mining and Environmental protection MEP, 24 – 27 May 2023, Sokobanja, Serbia, Belgrade : University of Belgrade-Faculty of mining and geology (2023)
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Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering
Josip Išek, Lazar Kaluđerović, Nikola Vuković, Maja Milošević, Ivana Vukašinović, Zorica Tomić (2020)... (63keV) and/or "Pa (1000 keV). The ecay products of ? Ra, _ Bi (609, 1120 and 1764keV) and "Pb (295 and 352 keV) were used for activity determination. The activity of 52 Th was calculated using its daughter product ŠAc (338 and 911 keV). K was determined from its single line of 1460 keV -energy. The ...
... recrystallized (purified) gypsum, insoluble residue and supernatant. Both raw phosphogypsum and recrystallized gypsum were examined using induct- ively coupled plasma optical emission spectrometry, X-ray diffraction and scanning electron microscopy with energy-dispersive spec- trometry. The activity conc ...
... Protection and Management of NORM Residues in the Phosphate Industry. Safety Reports Series No. 78. International Atomic Energy Agency, Vienna, Austria, 288 pp. Jalali J., Magdich S., Jarboui R., Loungou M. & Ammar E. (2016) Phosphogypsum biotransformation by aerobic bacterial flora and isolated ...Josip Išek, Lazar Kaluđerović, Nikola Vuković, Maja Milošević, Ivana Vukašinović, Zorica Tomić. "Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering" in Clay Minerals, Cambridge University press (2020). https://doi.org/10.1180/clm.2020.11
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Risk management in coal mining
Miljanović Igor, Milutinović Aleksandar, Tokalić Rade. "Risk management in coal mining" in Proceedings, 2nd Virtual International Conference on Science, Technology and Management in Energy, Niš:Research and Development Center “ALFATEC”, Niš, Serbia, and Complex System Research Centre (2016): 89-96
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Analysis of the exhaust emissions inventory from auxiliary mining machines
Stevan Đenadić, Aleksandar Mirković, Jovana Mitrović, Filip Miletić, Predrag Jovančić, Dragan Ignjatović (2023)Open-pit coal mines are equipped with a large number of mining machines and vehicles with diesel engines. Due to common daily operation of these machines and vehicles large amounts of exhaust gases which contain numerous pollutants are emitted into the atmosphere. The demand to reduce air pollution induced the activities in developed countries to map and calculate all gases emitted by industries to formulate and select adequate preventive activities. In collaboration with machine manufacturers, emission standards for off-road machines ...Stevan Đenadić, Aleksandar Mirković, Jovana Mitrović, Filip Miletić, Predrag Jovančić, Dragan Ignjatović. "Analysis of the exhaust emissions inventory from auxiliary mining machines" in 9th International Conference Mining and Environmental Protection, University of Belgrade, Faculty of Mining and Geology (2023)
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Hydrodynamic Model of The Open-Pit Mine “Buvač” (Republic of Srpska, Bosnia And Herzegovina)
Bajić Dragoljub, Polomčić Dušan, Papić Petar, Stojković Jana. "Hydrodynamic Model of The Open-Pit Mine “Buvač” (Republic of Srpska, Bosnia And Herzegovina)" in CD Proceedings of 6th Dubrovnik Conference on Sustainable Development of Energy Water and Environmental Systems,, Dubrovnik: (2011): 25-29
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Conditions for efficiency of open pit medium voltage power transformers
Aleksandrović Snežana (2017)Aleksandrović Snežana. "Conditions for efficiency of open pit medium voltage power transformers" in 3rd Virtual International Conference on Science, Technology and Management in Energy no. 3, Niš, Serbia:Research and Development Center “ALFATEC” (2017): 77-81
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Groundwater balance, natural recharge and drainage zones at open pit mine „Polje E“ of Kolubara Coal Basin (Republic of Serbia)
Polomčić Dušan, Bajić Dragoljub, Ristić-Vakanjac Vesna. "Groundwater balance, natural recharge and drainage zones at open pit mine „Polje E“ of Kolubara Coal Basin (Republic of Serbia)" in CD Proceedings of 7th Conference on Sustainable Development of Energy Water and Environmental Systems, Ohrid: (2012): 236-237
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Introduction to special section: Characterization of hydrocarbon and geothermal resource potential and carbon sequestration opportunities of the Pannonian Basin
Balázs Németh, Gábor Tari, Gábor Bada, Dejan Radivojević, Bruno Tomljenovic, Csaba Krézsek. "Introduction to special section: Characterization of hydrocarbon and geothermal resource potential and carbon sequestration opportunities of the Pannonian Basin" in Interpretation, AAPG SEG (2018). https://doi.org/10.1190/INT-2017-1207-SPSEINTRO.1
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Significance of dependability concept for electricity security of supply
Tanasijević Miloš, Ivezić Dejan, Jovančić Predrag, Madžarević Aleksandar. "Significance of dependability concept for electricity security of supply" in 6th International Scientific Conference on Energy and Climate Change 1, Athens, Greece:National and Kapodistrian University of Athens (2013): 113-120
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Ni–Sn coatings as cathodes for hydrogen evolution in alkaline solution. Chemical composition, phase composition and morphology effects
Jović Vladimir, Lačnjevac Uroš, Jović Borka, Karanović Ljiljana, Krstajić Nedeljko.. "Ni–Sn coatings as cathodes for hydrogen evolution in alkaline solution. Chemical composition, phase composition and morphology effects" in International journal of hydrogen energy 37 no. 23, Radarweg 29; Amsterdam, 1043 NX; Netherlands:Elsevier BV (2012): 17882-17891. https://doi.org/10.1016/j.ijhydene.2012.09.110
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Identification of a novel series of benzohopanes and its geochemical significance
Nytoft H. Peter, Vuković Nikola, Kildahl-Andersen Geir, Rise Frode, Životić Dragana, Stojanovic Ksenija (2016)Nytoft H. Peter, Vuković Nikola, Kildahl-Andersen Geir, Rise Frode, Životić Dragana, Stojanovic Ksenija. "Identification of a novel series of benzohopanes and its geochemical significance" in Energy & Fuels 30 no. 7, Washington:American Chemical Society (2016): 5563-5575. https://doi.org/10.1021/acs.energyfuels.6b0079
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Assessment of vulnerability of natural gas supply in Serbia: State and perspective
Madžarević Aleksandar, Ivezić Dejan, Živković Marija, Tanasijević Miloš, Ivić Milica. "Assessment of vulnerability of natural gas supply in Serbia: State and perspective" in Energy Policy 121, :Elsevier (2018): 415-425
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Study of the Synergetic Effect of Co-Pyrolysis of Lignite and High-Density Polyethylene Aiming to Improve Utilization of Low-Rank Coal
Ivan Kojić, Achim Bechtel, Nikoleta Aleksić, Dragana Životić, Snežana Trifunović, Gordana Gajica, Ksenija Stojanović (2021)... Effects of plastic wastes on coal pyrolysis behavior and the structure of semicokes. J. Anal. Appl. Pyrolysis 2005, 74, 327–336. [CrossRef] 37. Zhou, L.; Luo, T.; Huang, Q. Co-pyrolysis characteristics and kinetics of coal and plastic blends. Energy Convers. Manag. 2009, 50, 705–710. [CrossRef] 38. Chunmei ...
... source of energy. Keywords: lignite; HDPE; co-pyrolysis; synergetic effect 1. Introduction Production of energy in Serbia is based on coal (50%), particularly lignite (92% of total coal resources) [1]. The main lignite deposits in Serbia are of Upper Miocene age. They are located in Kolubara and Kostolac ...
... source of energy. Keywords: lignite; HDPE; co-pyrolysis; synergetic effect 1. Introduction Production of energy in Serbia is based on coal (50%), particularly lignite (92% of total coal resources) [1]. The main lignite deposits in Serbia are of Upper Miocene age. They are located in Kolubara and Kostolac ...Ivan Kojić, Achim Bechtel, Nikoleta Aleksić, Dragana Životić, Snežana Trifunović, Gordana Gajica, Ksenija Stojanović. "Study of the Synergetic Effect of Co-Pyrolysis of Lignite and High-Density Polyethylene Aiming to Improve Utilization of Low-Rank Coal" in Polymers, MDPI AG (2021). https://doi.org/10.3390/polym13050759