Претрага
27 items
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Non-Detonating Chemical Mixture for Non-Invasive Methods of Rock Breaking
Within the Innovation developed several different non-detonating chemical mixtures for non-invasive methods of rock breaking. Laboratory and polygon tests gave the satisfactory results and knowledge enough to start the practical experiments in the field. The basis of this innovation is a theoretical assumption that certain chemical mixtures release a large quantity of gases during combustion. If these gases are found in the enclosed space a growing pressure on the walls of the chamber in which combustion takes place will ...Lazar Kričak, Milanka Negovanović, Nikola Simić, Stefan Milanović. "Non-Detonating Chemical Mixture for Non-Invasive Methods of Rock Breaking" in X International Scientific Congress Innovations 2024, Varna, Bulgaria, 24-27. jun 2024, Scientific Technical Union of Mechanical Engineering "Industry 4.0" (2024)
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Hydraulic impact of pressure transients from water conveyance tunnel on the complex hydrogeological system: A case study HPP
Tunel pod pritiskom, Unutrašnji pijezometri, Tranzijenti pritiska, Karstna izdan, Pukotinska izdan, Hidraulički odzivIgor Jemcov, Maja Todorović, Aleksandar Jemcov, Marina Ćuk Đurović. "Hydraulic impact of pressure transients from water conveyance tunnel on the complex hydrogeological system: A case study HPP" in Journal of Hydrology, Pirot, 2024, Elsevier BV (2024). https://doi.org/10.1016/j.jhydrol.2024.132068
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Design and drilling of wells in formations with high pressure
Vojin Solomun (2024)Objectives of this Thesis are to: - Develop an awareness of the challenges presented from elevated temperatures and pressures in well construction. - Learn the key differences between ―normal‖ condition wells and HPHT wells. - Understand some of the indicators of thermal- and pressure-related problems. - Understand the responses which may be made to mitigate high pressure and high temperature ,,HPHT‘‘ challenges while drilling wells. HPHT wells are an unavoidable consequence of the ever expanding search for oil and gas resources around the world. As wells are ...Vojin Solomun. Design and drilling of wells in formations with high pressure, 2024
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Correlation of metabasic rocks from metamorphic soles of the Dinaridic and the Western Vardar zone ophiolites (Serbia) : three contrasting pressure-temperature-time paths
Срећковић Батоћанин Даница, Васковић Нада, Матовић Весна, Гајић Виолета. "Correlation of metabasic rocks from metamorphic soles of the Dinaridic and the Western Vardar zone ophiolites (Serbia) : three contrasting pressure-temperature-time paths" in Геолошки анали Балканског полуострва = Annales geologiques de la Peninsule Balkanique no. 73, Belgradе:Department of Geology and Department of Palaeontology, Faculty of Mining and Geology, University of Belgrade (2012): 61-85. https://doi.org/10.2298/GABP1273061S
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Productivity improvement with use of beam gas compressor: pilot test in Southeastern Europe mature field
Most of the wells in the oilfield Turija are operating with sucker rod pumps, where casing pressure at around 15 bar, and with marginal production rates. The high value of casing pressure indicates high pressure on the face of the formation and depends directly on well productivity. In addition, with increasing value of the casing pressure gas column in the annulus is moving the dynamic fluid level near pump intake and more gas is entering the pump, it results ...beam gas compressor, BGC, increase productivity, sucker rod pump, SRP, mature field, artificial lift, production optimisationBojan Martinović, Dušan Danilović, Branko Grubač, Robert Fadiga. "Productivity improvement with use of beam gas compressor: pilot test in Southeastern Europe mature field" in International Journal of Oil Gas and Coal Technology (2022)
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Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)
Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović (2014)Sphene (CaTiSiO5), a calcium titanosilicate ceramic has been prepared from a powder mixture of CaCO3, TiO2 and SiO2 using vibro-milling for homogenization and activation of precursors. During the highpressure and high-temperature synthesis (HPS) process at 4 GPa and 1,200 °C, sphene undergoes into phase transition, from room-temperature phase P21/a to high-temperature phase A2/a. Evidence of that structural phase transition is given in this paper using infrared, Raman spectroscopy and X-ray powder diffraction. Rietveld refinement was employed to get the ...Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović. "Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)" in Physics and Chemistry of Minerals, Springer Science and Business Media LLC (2014). https://doi.org/10.1007/s00269-014-0693-x
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A methodology for assessing the pressures on transboundary groundwater quantity and quality – experiences from the Dinaric karst
Zoran Stevanović, Veljko Marinović (2020)A relatively novel and abridged methodology for assessing the quantity and quality status of groundwater bodies has been applied in the Dinaric karst of SE Europe. Validation of pressure on quantity is based on groundwater budgeting and the correlation of available groundwater reserves and projected water demands, while pressure on quality is estimated by GIS-created maps: vulnerability – hazard – risk. The results obtained from the studied groundwater bodies indicate mostly low pressure on water quantity, but increased risk from diffuse and point pollution sources. ...Zoran Stevanović, Veljko Marinović. "A methodology for assessing the pressures on transboundary groundwater quantity and quality – experiences from the Dinaric karst" in Geologia Croatica, Croatian Geological Survey (2020). https://doi.org/10.4154/gc.2020.08
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The origin of Na-alkaline lavas revisited: new constraints from experimental melting of amphibole-rich metasomes+lherzolite at uppermost mantle pressure
We present a new experimental dataset for reaction experiments between natural amphibole-clinopyroxene metasomes (hornblendite) and synthetic lherzolite that produced Na-rich alkaline melts. Experiments were conducted at 1, 3 and 4 GPa and 1000–1300 °C. The generated melts range from foidite over basanite to phonotephrite. At 1 GPa between 1000 and 1100 °C amphibole decompression-breakdown products generate a phonotephritic melt. Among the breakdown components rhönite was found to be stable up to 1100 °C and 1 GPa. At 3 and ...аlkalni vulkanizam, еksperimentalna petrologija, кersutit, Kula vulkan, хornblendit, metasomatizam omotačaTobias Grützner, Dejan Prelević, Jasper Berndt, Stephan Klemme. "The origin of Na-alkaline lavas revisited: new constraints from experimental melting of amphibole-rich metasomes+lherzolite at uppermost mantle pressure" in Contributions to Mineralogy and Petrology (2023). https://doi.org/10.1007/s00410-023-02052-6
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Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans
Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović. "Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans" in Carbonates and Evaporites, Springer Science and Business Media LLC (2021). https://doi.org/10.1007/s13146-021-00754-1
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Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans
Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović. "Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans" in Carbonates and Evaporites, Springer Science and Business Media LLC (2022). https://doi.org/10.1007/s13146-021-00754-1
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Karst groundwater quantity assessment and sustainability: the approach appropriate for river basin management plans
Veljko Marinović, Zoran Stevanović (2019)As a result of the fact that karstified rocks can accumulate large amounts of high-quality groundwater, karst aquifer is considered, throughout the world, one of the most important types of aquifers. Due to their high permeability, but also vulnerability to pollution, these precious groundwater resources need to be properly evaluated and protected. Taking into account heterogeneity and complexity of the karst environment, it is difficult to propose a uniform algorithm for managing karst groundwater, which causes the necessity to ...Upravljanje karstnim podzemnim vodama, Pritisci na kvantitet voda, Plan upravljanja vodnim resursima, Bosna i Hercegovina, SrbijaVeljko Marinović, Zoran Stevanović. "Karst groundwater quantity assessment and sustainability: the approach appropriate for river basin management plans" in Environmental Earth Sciences, Springer Science and Business Media LLC (2019). https://doi.org/10.1007/s12665-019-8364-3
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Application of Expansive Mortars for the Formation of Artificial Screens During Blasting in Urban Areas
During construction of buildings in urban areas, sometimes there is a need to blast solid rock mass in the immediate vicinity of the surrounding buildings. In that case, the aim is not only to increase the efficiency of blasting, but also to reduce harmful effects of ground vibration induced by blasting. At the same time, it is very important to protect the buildings located in the safe zone from the blast site as well as remaining rock mass around ...Milanka Negovanović, Lazar Kričak, Stefan Milanović, Nikola Simić, Jelena Majstorović. "Application of Expansive Mortars for the Formation of Artificial Screens During Blasting in Urban Areas" in 31st International Conference Ecological Truth & Environmental Research-EcoTER'24, Sokobanja, 18-21. jun 2024, Bor : Tehnički fakultet u Boru (2024)
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Hidraulički tranzijenti u karstnoj sredini tokom rada hidroelektrane
Maja Todorović, Marina Ćuk Đurović, Igor Jemcov. "Hidraulički tranzijenti u karstnoj sredini tokom rada hidroelektrane" in Knjiga apstrakata 10. Simpozijuma o zaštiti karsta, Zlatibor, 14-15. oktobar 2023., Beograd : Akademski speleološko–alpinistički klub (ASAK) (2023)
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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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Kontaktni metamorfizam gornjokrednih sedimentnih stena Rudnika
Kostić N. Bojan (2021)Kontaktni metamorfizam gornjokrednih sedimentnih stena na planini Rudnik ispitivan je na uzorcima iz pet bušotina. Definisano je šest varijeteta krednih stena (protolita) koji čine dve litološke jedinice izgrađene od klastičnog, karbonatnog i klastično-karbonatnog materijala. Vulkanskom aktivnosti na Rudniku formirana su vulkanska tela koja se utiskuju duž slojevitosti sedimentnih stena, a neka ih presecaju u vidu dajkova. Starost ovog vulkanskog događaja određena je na 23.9 miliona godina. Ovaj miocenski vulkanizam doveo je do kontaktno metamorfnih promena sedimentnih stena i obrazovanja skarnova ...Kostić N. Bojan. Kontaktni metamorfizam gornjokrednih sedimentnih stena Rudnika, Univerzitet u Beogradu, Rudarsko-geološki fakultet, 2021
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Uticaj utiskivanja gas-lift gasa na prenos mase i toplote
Branko Grubač (2019)Nakon uvođenja kontinualnog gas-lifta, primećen je porast proizvodnje tečnog naftnog gasa, TNG, u postrojenju za preradu gasa, kao jednog od finalnih proizvoda dobijenog iz fluida gaso kondenzatnih i rastvorenog gasa iz naftnih bušotina. Pretpostavljeno je da se prisustvom gas-lift gasa uspostavlja drugačija ravnoteža faza u odnosu na slučaj bez gaslifta, te da je gas-lift gas stripovao propan i butane iz tečne u parnu fazu, što je dovelo do povećanja prinosa TNG-a. Napravljen je model bušotine koja radi u kontinualnom gas-liftu ...Branko Grubač. Uticaj utiskivanja gas-lift gasa na prenos mase i toplote, Beograd : Rudarsko-geološki fakultet, 2019
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Стратешко планирање функционалности подземних просторија моделом прогнозе деформација
Лука Црногорац (2023)Релативно велике деформације подградне конструкције у подземним рудницима угља у Републици Србији представљају један од главних проблема за постизање планиране производње угља. Деформације подграде су директна последица статичких и динамичких оптерећења стенске масе и у многоме зависе и од времена трајања изложености подграде утицају подземног притиска. Код ниско механизованог радног процеса долази до повећаног излагања подземних просторија утицају подземног притиска услед дугог производног циклуса који је често пропраћен застојима у раду. Веома често подземне просторије се санирају и по ...Лука Црногорац. Стратешко планирање функционалности подземних просторија моделом прогнозе деформација, Београд : [Л. Црногорац], 2023
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Natural two-dimensional pyrophyllite: Nanoscale lubricant, electrical insulator and easily-machinable material
Borislav Vasić, Radoš Gajić, Ivana Milošević, Žarko Medić, Marina Blagojev, Marko Opačić, Aleksandar Kremenović, Dejan Lazić (2022)Pyrophyllite, with the chemical formula Al2Si4O10(OH)2, is a naturally occurring and abundant van der Waals mineral belonging to the group of phyllosilicates. It is very soft, layered crystal used for sculpting and an excellent electrical and thermal insulator aimed for the operation at high pressure and temperature. Here, for the first time, two-dimensional (2D) pyrophyllite obtained by both mechanical and liquid phase exfoliation is presented and investigated at the nanoscale. The layered structure provides low friction coefficient of around ...Atomic force microscopy, Insulating properties, Nanofriction and wear, Natural two dimensional materials, Phyllosilicates, PyrophylliteBorislav Vasić, Radoš Gajić, Ivana Milošević, Žarko Medić, Marina Blagojev, Marko Opačić, Aleksandar Kremenović, Dejan Lazić. "Natural two-dimensional pyrophyllite: Nanoscale lubricant, electrical insulator and easily-machinable material" in Applied Surface Science, Elsevier BV (2022). https://doi.org/10.1016/j.apsusc.2022.155114
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A Computer-Aided System for Design of Drainage Facilities in Surface Mining
Sistemi za odvodnjavanje u velikim površinskim kopovima su projektovani da ostvare tri osnovna cilja: održavanje radnih uslova suvim, stabilnim i bezbednim; smanjenje hidrostatskog pritiska i povećanje efektivnog naprezanja tla radi poboljšanja stabilnosti kosina; i obezbeđivanje radne površine. Ovo se može postići pomoću drenažnih objekata koji uključuju kanale, jame za sakupljanje vode i pumpne stanice. U radu se prikazuje razvoj kompjuterski potpomognutog sistema pod nazivom Devatering of Open Pit Mines (DEVOP), koji može pomoći projektantima površinskih kopova da reše probleme ...Vladislav Kecojević, Marek Mrugala, Radomir Simić, Ranka Stanković. "A Computer-Aided System for Design of Drainage Facilities in Surface Mining" in Mine Water and the Environment, Springer Nature Switzerland AG (2003). https://doi.org/10.1007/s10230-003-0015-x
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A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers
Effectiveness evaluation is one of the basic components of engineering asset management and maintenance engineering in general. Effectiveness is an overall concept representing a measurement of quality of service level for the analyzed engineering system. This concept contains a series of partial indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model ...Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić. "A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers" in International Journal of Industrial Engineering: Theory, Applications and Practice (2019)