Претрага
320 items
-
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)
-
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)... content (29.77% dry basis; 56.30 dry, ash-free basis), low net calorific value (12.1 MJ/kg), and high ash content (47.12%), allowing to study the influence of HDPE on the low-quality lignite. Lignite was crushed and pulver- ized to <63 µm. Prior to pyrolysis experiments, extractable organic matter (bitumen) ...
... further heating. The elemental analysis and calculated calorific values of solid residues of lignite/HDPE mixtures (Section 3.3.) also indicate no influence with heating above 500 ◦C. The mentioned results are consistent with TGA data, which showed that, at temperatures >500 ◦C, there is almost no impact ...
... 4. Net calorific value of lignite residues continuously increases with the rise in temperature, whereas for lig- nite/HDPE mixture residues, the influence of pyrolysis temperature was less pronounced, and the greatest values are detected at 500 ◦C. Net calorific values of lignite/HDPE mixture residues ...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
-
The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)
... reactivity (instant response of observation well PP-3) while the tunnel was online, when both the tunnel and the hydrogeologic environment were under the influence of the pressure of the transported water (Figure 5). In the full operating mode of the HPP (4–5 h/day), at PP-3 the transport of water relieved the ...
... Na–Cl through Na–HCO3 to Ca(Mg)–HCO3, indicated that the heterogeneity of the bedrock and changes in the tunnel’s operating regime had a considerable influence on the hydrochemical conditions. In the final stages of tunnel prospecting, the highest EC and water temperatures, and the lowest ORP were recorded ...Marina Čokorilo Ilić, Ana Mladenović, Marina Ćuk, Igor Jemcov. "The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)" in Water, MDPI AG (2019). https://doi.org/10.3390/w11030603
-
A Fuzzy Expert Model for Availability Evaluation
Each technical system within itself carries the great potential danger of possible occurrence of failure and damages. Mining machines are characteristic by great investment values, costs of unplanned shutdowns, complex working conditions, and environment and workers hazards. Systematic monitoring of the mining machinery is of great importance for the management of the mining companies. Availability is the overall concept of quality of service. Includes information regard to operating state, an idle state, a standby state and shut down. The ...... by quantitative indicators, and these indicators are measures of dependability and quality of service. Availability performance has a decisive influence on the dependability and the quality of service due to the known fact that the machine must be primarily available for operation in order to obtain ...
... provide the availability structure. Delays caused by completing paperwork, waiting for manpower, tools, test equipment or waiting for spares have an influence on machine availability but mostly they are not noted. Therefore, for providing relevant information about the availability of machines a significant ...Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić. "A Fuzzy Expert Model for Availability Evaluation" in Proceedings of the 2019 20th International Carpathian Control Conference (ICCC), AGH University of Science and Technology, Kraków - Wieliczka, Poland (2019)
-
Површинско распадање керсантита из Тешића мајдана у корелацији са начином обраде на примеру малог степеништа (Београдска тврђава)
Невенка Новаковић (2024)Архитектуру Београда на прелазу 19. у 20. век обележила је употреба керсантита из каменолома Тешића мајдана. Kao камен високих декоративних својстава, керсантит је коришћен за јавне споменике, делове или потпуну изградњу објеката (Народна скупштина Србије, Мало степениште, Народни музеј и др.). Како очување споменика културе изискује познавање својстава уграђеног камена, истраживања су обухватила детаљно проучавање петролошких, хемијских и физичких карактеристика керсантита из Тешића мајданa и узорака камена из споменика Мало степениште (студија случаја). Након детаљног мапирања стања керсантита, лабораторијских ...керсантит, Мало степениште, споменик културе, архитектонски камен, физичко-хемијско распадање, мапирање, форме распадања, површинска обрадаНевенка Новаковић. Површинско распадање керсантита из Тешића мајдана у корелацији са начином обраде на примеру малог степеништа (Београдска тврђава), Београд : [Н. Новаковић], 2024
-
Application of ERT in the study of debris-flow source area: Case study Selanac debris flow
Dragana Đurić, Jelka Krušić, Biljana Abolmasov. "Application of ERT in the study of debris-flow source area: Case study Selanac debris flow" in 11th Congress of the Balkan Geophysical Society, Volume 2021, Online-Romania, 10 -14. Oct 2021,, European Association of Geoscientists & Engineers (2021). https://doi.org/10.3997/2214-4609.202149BGS15
-
An arid phase in the Internal Dinarides during the early to middle Miocene: Inferences from Mg-clays in the Pranjani Basin (Serbia)
N. Andrić-Tomašević, V. Simić, O. Mandic, D. Životić, M. Suárez, E. García-Romero. "An arid phase in the Internal Dinarides during the early to middle Miocene: Inferences from Mg-clays in the Pranjani Basin (Serbia)" in Palaeogeography, Palaeoclimatology, Palaeoecology, Elsevier BV (2020). https://doi.org/10.1016/j.palaeo.2020.110145
-
Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector
To strengthen the security of supply of the Serbian gas sector, it is necessary to analyze the impact of planned strategic measures. The analysis involves the identification of the most influential threats to the security of natural gas supply and prioritization of the strategic measures for overcoming the consequences of threats. The proposed methodology is based on Fuzzy Analytic Hierarchy Process. The obtained weights for the identified threats and strategic measures are formed according to experts' judgments. The results ...Sigurnost snabdevanja, Donošenje odluka, Snabdevanje prirodnim gasom, Fazi AHP, Energetski indikatoriBoban Pavlović, Dejan Ivezić, Marija Živković. "Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector" in Energy Policy, Elsevier BV (2020). https://doi.org/10.1016/j.enpol.2020.111936
-
Comprehensive Profiling of Microbiologically Induced CaCO3 Precipitation by Ureolytic Bacillus Isolates from Alkaline Soils
Olja Šovljanski, Lato Pezo, Jovana Stanojev, Branimir Bajac, Sabina Kovač, Elvira Tóth, Ivan Ristić, Ana Tomić, Aleksandra Ranitović, Dragoljub Cvetković, Siniša Markov (2021)MICP process, kinetic study, calcite, vaterite, MALDI-TOF identification, Bacillus licheniformis, Sporosarcina pasteurii... , calcium concentration). The described behavior is similar for all tested bacteria, which can suggest that the kinetic of ureolysis has a great influence on the MICP process, regardless of the ureolytic bacterial strain. Table 1 also summarizes the regression coefficients of the observed mathematical ...
... deposits, the obtained precipitates (after the first and at the last incubation day) were subjected to structural characterization to observe the influence of incubation time on crystal forma- tion, maturation, and morphology. The precipitates were first studied by using FTIR spectroscopy and X-ray d ...
... through calcium carbonate precipitation by Sporosarcina pasteurii and Bacillus subtilis. Crystals 2018, 8, 189. [CrossRef] 51. Peng, J.; Liu, Z. Influence of temperature on microbially induced calcium carbonate precipitation for soil treatment. PLoS ONE 2019, 14, e0218396. [CrossRef] 52. Heveran, C ...Olja Šovljanski, Lato Pezo, Jovana Stanojev, Branimir Bajac, Sabina Kovač, Elvira Tóth, Ivan Ristić, Ana Tomić, Aleksandra Ranitović, Dragoljub Cvetković, Siniša Markov. "Comprehensive Profiling of Microbiologically Induced CaCO3 Precipitation by Ureolytic Bacillus Isolates from Alkaline Soils" in Microorganisms, MDPI AG (2021). https://doi.org/10.3390/microorganisms9081691
-
Hydrochemical changes and groundwater grouping data by multivariate statistical methods within one karst system: recharge–discharge zone (Eastern Serbia case study)
Ljiljana Vasić, Dragana Živojinović, Vladana Rajaković-Ognjanović. "Hydrochemical changes and groundwater grouping data by multivariate statistical methods within one karst system: recharge–discharge zone (Eastern Serbia case study)" in Carbonates and Evaporites, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s13146-019-00548-6
-
Моделирање утицаја одступања линије најмањех отпора од пројектоване на интензитет потреса од минирања
Стефан Милановић (2024)Према дефиницији линија најмањег отпора представља најкраће растојање од центра минског пуњења до слободне површине. Oвим истраживањем представљен је утицај линије најмањег отпора, као и њеног одступања од пројектоване на интезитет потреса услед минирања. Проблем линије најмањег отпора је веома заступљен у пракси, где се занемарује изглед слободне површине, који може бити врло неправилан. Линију најмањег отпора је потребно мерити целом дужином минске бушотине према слободној површини, иако је у пракси случај да се мери најчешће као растојање од ...линија најмањег отпора, 3D модел, потреси услед минирања, минирање, слободна површина, метода раздвојених елеменатаСтефан Милановић. Моделирање утицаја одступања линије најмањех отпора од пројектоване на интензитет потреса од минирања, Београд : [С. Милановић], 2024
-
Uticaj geološke neizvesnosti u razvoju rudarskih projekata
Rudarstvo je industrija koja se nosi sa različitim vrstama neizvesnosti i rizika zbog svoje prirode i specifičnosti. Neizvesnost u rudarstvu može poticati iz različitih izvora i uticati na različite aspekte rudarskih projekata. Kao jedan od dominantnih faktora, ističe se geološka neizvesnost. Geološka neizvesnost igra ključnu ulogu u rudarstvu i može značajno uticati na procenu resursa i rezervi, planiranje eksploatacije, ekonomsku isplativost i upravljanje rizicima. Ova neizvesnost se ne može eliminisati, ali se uz primenu adekvatnih standarda i zakona može ...... Through this paper, the differences in regional and foreign practice from the aspect of categorization of resources and reserves, as well as the influence of the degree of reliability of the geological characteristics of the deposit on the results of the pit optimization, are shown. The analysis was ...Petar Marković, Dejan Stevanović, Mirjana Banković. "Uticaj geološke neizvesnosti u razvoju rudarskih projekata" in XI Međunarodna konferencija "Ugalj i kritični minerali 2023", CCM 2023, Zlatibor, 11-14. oktobar 2023., Beograd : Jugoslovenski komitet za površinsku eksploataciju (2023)
-
Mineralogical analysis of a clay body from Zlakusa, Serbia, used in the manufacture of traditional pottery
... (1911) Die Plastizitit der Tone. Internationale Mitteilungen der Bodenkunde, 1, 4–37. Baccour H., Medhioub M., Jamoussi F. & Mhiri T. (2009) Influence of firing temperature on the ceramic properties of Triassic clays from Tunisia. Journal of Materials Processing Technology, 209, 2812–2817. ...
... on of clayey raw materials for ceramic manufacture in ancient Sicily. Applied Clay Science, 53, 476–488. Monterio S.N. & Vieira C.M.F. (2004) Influence of firing temperature on the ceramic properties of clays from Campos dos Goytacazes, Brazil. Applied Clay Science, 27, 229-234. Moreno-Maroto ...Maja Milošević, Biljana Đorđević, Mihovil Logar. "Mineralogical analysis of a clay body from Zlakusa, Serbia, used in the manufacture of traditional pottery" in Clay Minerals (2020). https://doi.org/10.1180/clm.2020.20
-
Simulation of Hydrogeological Environmental Discharge in Case of Interruption Constant Observations
Marina Čokorilo Ilić, Dragoljub Bajić, Miroslav Popović. "Simulation of Hydrogeological Environmental Discharge in Case of Interruption Constant Observations" in International Scientific Conference - Sinteza 2024, Belgrade, 16. maj 2024, Singidunum University (2024). https://doi.org/10.15308/Sinteza-2024-288-294
-
Application of VIКOR method in the selection of an optimal splution of excavation “Borska Reka” ore deposit
Sanja Bajić, Dragoljub Bajić, Branko Glušćević, Radmila Gaćina. "Application of VIКOR method in the selection of an optimal splution of excavation “Borska Reka” ore deposit" 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)
-
Freeze-dried nanocrystal dispersion of novel deuterated pyrazoloquinolinone ligand (DK-I-56-1): Process parameters and lyoprotectant selection through the stability study
Jelena R. Mitrović, Maja Bjelošević Žiberna, Aleksandar Vukadinović, Daniel E. Knutson, Dishary Sharmin, Aleksandar Kremenović, Pegi Ahlin Grabnar, Odon Planinšek, Dominique Lunter, James M. Cook, Miroslav M. Savić, Snežana D. Savić (2023)Recently, nanocrystal dispersions have been considered as a promising formulation strategy to improve the bioavailability of the deuterated pyrazoloquinolinone ligand DK-I-56-1 (7‑methoxy-2-(4‑methoxy-d3-phenyl)-2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one). In the current study, the freeze-drying process (formulation and process parameters) was investigated to improve the storage stability of the previously developed formulation. Different combinations of lyoprotectant (sucrose or trehalose) and bulking agent (mannitol) were varied while formulations were freeze-dried under two conditions (primary drying at -10 or -45 °C). The obtained lyophilizates were characterized in terms ...... ing, lyoprotectants are added at different concentrations. The type and concentration of these excipients have been shown to have a strong influence on redispersibility (Jakubowska et al., 2022), so screening of lyoprotectants was the first step of the preliminary study. The formu- lation of ...
... the wavenumber of the OH-stretching band (Sri- tham and Gunasekaran, 2017), the moisture content was similar in all samples (about 3%), so its influence could be excluded when comparing different freeze-dried samples. The FT-IR spectrum of trehalose dihydrate in bulk was typical for crystalline ...
... s. J. Drug Deliv. Sci. Technol. 74, 103528 https://doi.org/10.1016/j.jddst.2022.103528. Jena, S., Suryanarayanan, R., Aksan, A., 2016. Mutual influence of mannitol and trehalose on crystallization behavior in frozen solutions. Pharm. Res. 33, 1413–1425. https://doi.org/10.1007/s11095-016-1883-7 ...Jelena R. Mitrović, Maja Bjelošević Žiberna, Aleksandar Vukadinović, Daniel E. Knutson, Dishary Sharmin, Aleksandar Kremenović, Pegi Ahlin Grabnar, Odon Planinšek, Dominique Lunter, James M. Cook, Miroslav M. Savić, Snežana D. Savić. "Freeze-dried nanocrystal dispersion of novel deuterated pyrazoloquinolinone ligand (DK-I-56-1): Process parameters and lyoprotectant selection through the stability study" in European Journal of Pharmaceutical Sciences, Elsevier BV (2023). https://doi.org/10.1016/j.ejps.2023.106557
-
Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling
Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeBranislav Petrović, Veljko Marinović, Zoran Stevanović. "Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling" in Environmental Earth Sciences, Springer Science and Business Media LLC (2023). https://doi.org/10.1007/s12665-023-10911-5
-
Influence of paleoenvironmental conditions on distribution and relative abundance of saturated and aromatic hydrocarbons in sediments from the NW part of the Toplica basin, Serbia
Nikola Burazer, Aleksandra Šajnović, Nebojša Vasić, Milica Kašanin-Grubin, Dragana Životić, João Graciano Mendonça Filho, Predrag Vulić, Branimir Jovančićević (2020)Nikola Burazer, Aleksandra Šajnović, Nebojša Vasić, Milica Kašanin-Grubin, Dragana Životić, João Graciano Mendonça Filho, Predrag Vulić, Branimir Jovančićević. "Influence of paleoenvironmental conditions on distribution and relative abundance of saturated and aromatic hydrocarbons in sediments from the NW part of the Toplica basin, Serbia" in Marine and Petroleum Geology, Elsevier BV (2020). https://doi.org/10.1016/j.marpetgeo.2020.104252
-
Trans-Lithospheric Diapirism as a Possible Mechanism for Ophiolite Emplacement?
Nikola Stanković, Taras Gerya, Vladica Cvetković, Vesna Cvetkov. "Trans-Lithospheric Diapirism as a Possible Mechanism for Ophiolite Emplacement?" in EGU General Assembly 2024, Vienna, 14-19 April 2024, Göttingen : Copernicus GmbH (2024). https://doi.org/10.5194/egusphere-egu24-568
-
Availability as a dimension of energy security in the Republic of Serbia
Boban Pavlović, Dejan Ivezić (2016)There is a range of modern approaches and models in literature for the evaluation and determination of energy security, which are based on different parameters and indicators. For most of them, a common characteristic is emphasizing the avail ability of energy, as an important dimension for ensuring energy security. In this paper, concise overview of Serbian energy sectors is given and appropriate energy indicators are defined and determined. Selected indicators provide insight into the main components that characterize availability ...... dealing with energy issues [1]. In many of these studies, availability of energy is pointed out as the most important dimension and with the greatest influence on the overall energy security [1-7]. In essence, availability represents the physical presence of energy re- sources, as well as possibility of ...
... energy price being at a level that will not adversely affect the eco- nomic performance of the economy. Thus, there are several factors that can influence the energy security [7]: – the availability of reserves, both indigenously and by foreign suppliers, – the ability of an economy to acquire ...Boban Pavlović, Dejan Ivezić. "Availability as a dimension of energy security in the Republic of Serbia" in Thermal Science, National Library of Serbia (2016). https://doi.org/10.2298/TSCI160923303P