Претрага
1270 items
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The State and Perspective of Belgrade District Heating System Development
Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Fethi Silajdžić, Samra Arnaut, Goran Đelić (2019)District heating (DH) system in Belgrade provides energy for heating of more than 21 million m2 in households (app. 50% of all households), public, commercial and industry sectors. Public Utility Company “Beogradske elektrane” is responsible for all segments of the DH system operation. The system is fueled mostly by natural gas. The share of renewables is negligible. The research analyzes effects of implementation of two main projects proposed in the Development Strategy of the PUC - the introduction of ...... District heating (DH) system in Belgrade provides energy for heating of more than 21 million m2 in households (app. 50% of all households), public, commercial and industry sectors. Public Utility Company “Beogradske elektrane” is responsible for all segments of the DH system operation. The system ...
... fuel mix in Belgrade DH system for the period until 2030 are presented supported with appropriate indicators (P/F ratio, import dependency, primary/final energy consumption, GHG and pollutants emissions). Projections are given and indicators are calculated for 4 different scenarios, analyzing different ...
... rs Dejan Ivezić is Professor in Energy and Sustainable Development at University of Belgrade – Faculty of Mining and Geology, Head of the Center for Energy. He has more than 20 years of experience in research and involvement in Serbian energy planning and policy making. The State and Perspective ...Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Fethi Silajdžić, Samra Arnaut, Goran Đelić . "The State and Perspective of Belgrade District Heating System Development" in 5th International Conference on Smart Energy Systems, Copenhagen : Aalborg Universitet (2019)
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Mineralogical analysis of a clay body from Zlakusa, Serbia, used in the manufacture of traditional pottery
... it for the next 24h. As the excess water is drained, the clay body is extracted onto a table, which will allow for its further prepar- ation and for the addition of calcite. The calcite pieces are first hammered to obtain smaller pieces and then ground in a fine grinding hammer mill, and for the ...
... the size of the vessel to be made. For example, for larger pots, such as celebration or wedding pots, the recipe involves 60% calcite and 40% clay (Djordjević, 2013). The next step is to mix the clay and calcite powder into a homogeneous mass that is ready for processing. From there, a piece of clay ...
... Table 3. Samples with PI <10% are not appropriate for the manu- facture of building-related items, and those with a PI >34% would be difficult to extrude (Barnes, 2014). The LL values for CIMx (55.2%) and ClBd (32.4%) are within the range defined for applica- tion in the manufacture of ceramics (30-60%) ...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
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Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source
Groundwater in a hard rock formation is most endangered at places where a potential source can discharge contaminants that can reach the saturated zone of an aquifer. In these circumstances, an essential tool for groundwater protection is the contamination risk map. This map is based on the integration of two maps: a hazards map, i.e., map of potential sources of contamination and a vulnerability map. The selection of a proper vulnerability method is an important task since the resulting ...karta rizika od kontaminacije, ranjivosti podzemnih voda, DRASTIC, EPIK, PI, COP, Nacionalni park TaraVladimir Živanović, Igor Jemcov, Veselin Dragišić. "Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source" in Geologia Croatica, Croatian Geological Survey (2022). https://doi.org/10.4154/gc.2022.23
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The preliminary selection of oil reservoir in Serbia for carbon dioxide injection and storage by a multicriteria decision-making approach: a case study
Lola Tomić, Vesna Karović Maričić, Dušan Danilović. "The preliminary selection of oil reservoir in Serbia for carbon dioxide injection and storage by a multicriteria decision-making approach: a case study" in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, Taylor & Francis (2021). https://doi.org/10.1080/15567036.2021.1936303
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Manganese-pyromellitate complex as a precursor for preparation of spinel Mn3O4
Lidija Radovanović, Željko Radovanović, Aleksandar Kremenović, Bojana Simović, Milica V. Vasić, Jelena Rogan (2022)In recent years, thermal decomposition studies of transition metal complexes with benzenepolycarboxylate ligands have become an area of a great importance due to the possibility of obtaining useful metal oxides with desirable electrical, magnetic and catalytic properties [1]. As a contrast to conventional methods for the preparation of metal oxides, such as hydrothermal or sol–gel treatment, thermolysis is faster, more efficient ...Lidija Radovanović, Željko Radovanović, Aleksandar Kremenović, Bojana Simović, Milica V. Vasić, Jelena Rogan. "Manganese-pyromellitate complex as a precursor for preparation of spinel Mn3O4 " in XIV Conference of chemists, technologists and environmentalists of Republic of Srpska, Academy of sciences and arts of the Republic of Srpska, Banja Luka, Republic of Srpska, B&H, October 21st-22nd, 2022, University in Banjaluka, Faculty of Technology (2022)
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History of the development of the hydrodynamic model of the open pit mine “Drmno”, Serbia
With the creation of a hydrodynamic model, the need for it usually ceases until some next moment when the model needs to be updated and used for the set task for the necessary project documentation or dedicated studies. It is relatively rare that almost every year the model is improved and used for forecast calculations. The paper presents the basic characteristics and development of the hydrodynamic model of the open pit mine “Drmno” for 25 years. This open pit ...Dušan Polomčić, Jelena Ratković, Vesan Ristić Vakanjac. "History of the development of the hydrodynamic model of the open pit mine “Drmno”, Serbia" in National Conference with International Participation “GEOSCIENCES 2023”, Review of the Bulgarian Geological Society , Sofia : Bulgarian Geological Society (2023)
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Karst aquifer as a buffer for climate variations and changes
Stevanović Zoran, Ristić-Vakanjac Vesna, Milanović Saša. "Karst aquifer as a buffer for climate variations and changes" in Proceedings / IWA Specialist Groundwater Conference, 08-10 September 2011, Belgrade, Serbia, Belgrade: Institute for the Development of Water Resources Jaroslav Èerni (2011): 369-375
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Photocatalytic degradation of textile dye with hydrothermally modified nanoanatase
Simović Bojana, Poleti Dejan, Kovač Sabina, Bjelajac Anđelika, Dapčević Aleksandra, Branković Goran (2015)Simović Bojana, Poleti Dejan, Kovač Sabina, Bjelajac Anđelika, Dapčević Aleksandra, Branković Goran. "Photocatalytic degradation of textile dye with hydrothermally modified nanoanatase" in 3rd Conference of the Serbian Society for Ceramic Materials 3rd Conference of the Serbian Society for Ceramic Materials 3rd Conference of the Serbian Society for Ceramic Materials, Beograd, Srbija :Institute for Multidisciplinary Research, University of Belgrade (2015): 82-82
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Improvement of Queries using a Rule Based Procedure for Inflection of Compounds and Phrases
Stanković Ranka (2008)Stanković Ranka. "Improvement of Queries using a Rule Based Procedure for Inflection of Compounds and Phrases" in POLIBITS, Research journal on Computer science and computer engineering with applications, Special section: Natural Langugage Processing, Journal of Research and Developement in Computer Science and Engeneering, ed. Grigori Sidorov no. 37, Mexico City, Mexico:Center for Technological Design and Development in Computer Science (CIDETEC) of the National Polytechnic Institute (IPN) (2008): 14-20
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Mechanosynthesis and structural characterization of nanocrystalline Ce1–Y O2– (x=0.1–0.35) solid solutions
Martin Fabián, Bratislav Antić, Vladimír Girman, Milica Vučinić-Vasić, Aleksandar Kremenović, Shigeru Suzuki, Horst Hahn, Vladimír Šepelák (2015)A series of nanostructuredfluorite-type Ce1–xYxO2–δ (0rxr0.35) solid solutions, prepared via highenergy milling of the CeO2/Y2O3mixtures, are investigated by XRD, HR-TEM, EDS and Raman spectroscopy. For thefirst time, complementary information on both the long-range and short-range structural features of mechanosynthesized Ce1–xYxO2–δ, obtained by Rietveld analysis of XRD data and Raman spectroscopy, is provided. The lattice parameters of the as-prepared solid solutions decrease with increasing yttrium content. Rietveld refinements of the XRD data reveal increase in microstrains in the host ceria ...Martin Fabián, Bratislav Antić, Vladimír Girman, Milica Vučinić-Vasić, Aleksandar Kremenović, Shigeru Suzuki, Horst Hahn, Vladimír Šepelák. "Mechanosynthesis and structural characterization of nanocrystalline Ce1–Y O2– (x=0.1–0.35) solid solutions" in Journal of Solid State Chemistry, Elsevier BV (2015). https://doi.org/10.1016/j.jssc.2015.06.027
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The influence of Al<sup>3+</sup>ion on porcine pepsin activity<i>in vitro</i>
The in vitro effect of Al3þ ions in the concentration range 1.7·1026M–8.7·1023M on pepsin activity at pH 2, via kinetic parameters and its electrophoretic mobility was evaluated. Kinetic study demonstrated the existence of an activation effect of Al3þ at pH 2 on pepsin molecule. Kinetic analysis with respect to concentrations of haemoglobin showed that Al3þ ions increase the maximal velocity (Vmax) and kcat values rather than apparent affinity for substrate (KS) implying the non-competitive nature of activation which indicated ...... are used for calculating equilibrium constants K,s and K,A for dissociation of formed binary enzyme-activator (AP' ) and ternary enzyme- activator-substrate complexes (Figure 3, Scheme 1). The calculated values for constants are 0.904 + 0.083 mM and 8.56 + 0.51 kM, respectively. For further ...
... respect- ively. Other constants, K,A = 8.56 + 0.51 M for binding of aluminium to pepsin-haemoglobin com- plex and Kws = 0.904 0.76 + 0.083mM for binding of haemoglobin to pepsin-aluminium complex are in agreement with proposed conditions for partially non- competitive activation mechanism. ...
... a. values rather than apparent affinity for substrate (Ks) implying the non-competitive nature of activation which indicated that aluminium wWas a non-essential activator of partial non-competitive type. The values of the equilibrium constants Ks and KA for dissociation of corresponding complexes ...Vesna M. Pavelkić, Kristina R. Gopcević, Danijela Z. Krstić, Marija A. Ilić. "The influence of Al3+ion on porcine pepsin activityin vitro" in Journal of Enzyme Inhibition and Medicinal Chemistry, Informa UK Limited (2008). https://doi.org/10.1080/14756360701841095
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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)... per minute is observed at 479.5 ◦C and 484.0 ◦C for the HDPE and lignite/HDPE mixture, respectively. The residual mass at 500 ◦C for lignite alone was 75%, and for HDPE alone was 4.79%, based on which the expected percentage of undecomposed residue for a mixture of lignite and HDPE (1:1) according to ...
... 40:1). The suspension was intensively shaken and left in a dark place for 16 h. The suspension was then refluxed for 20 min and filtered to separate asphaltenes. Asphaltene precipitate was rinsed several times with hot n-heptane for total removal of maltenes (n-heptane soluble fraction). Excess of n-heptane ...
... and their mixture) into liquid and gaseous products. However, the increase is much more prominent for HDPE and the lignite/HDPE mixture than for lignite alone. The greatest yield of liquid products for all three substrates is recorded at 500 ◦C, suggesting that, at higher temperatures, their further ...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
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Процјена хазарда и ризика од клизишта за различите нивое просторног планирања у Републици Српској, БиХ
Цвјетко С. Сандић (2022)Територија Републике Српске је у посљедних десетак година веома угрожена активирањем нових и реактивирањем старих клизишта. Она својим дјеловањем наносе огромне материјалне штете, па и људске жртве, те је неопходно озбиљније третирање и дјеловање у борби са овим природним хазардом. Чест проблем јесте одговорност, тј. надлежност институција из ове области и недостатак у законској регулативи која готово никако или само површно обрађује област хазарда и ризика од клизишта. Усљед непостојања праксе и усвојених методологија које су у примјени у свијету, циљ ...Цвјетко С. Сандић. Процјена хазарда и ризика од клизишта за различите нивое просторног планирања у Републици Српској, БиХ, Београд : [Ц. Сандић], 2022
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Flotability of chalcopyrite from the Rudnik deposit
Директно селективно флотирање олова, бакра и цинка у флотацији рудника „Рудник” датира од 1984. године. Технолошка шема омогућава директно издвајање селективних концентрата у три циклуса. У првом циклусу се издваја минерал олова (галенит), док су минерал бакра (халкопирит) и минерал цинка (марматит) депримирани. У другом циклусу се оток концентрације минерала олова кондиционира и припрема за издвајање минерала бакра. Након кондиционирања, у овом циклусу се издваја минерал бакра. У трећем циклусу се оток концентрације минерала бакра кондиционира и припрема за ...Đurica Nikšić, Predrag Lazić, Milena Kostović. "Flotability of chalcopyrite from the Rudnik deposit" in Journal of Mining Science, Springer Verlag (2021). https://doi.org/10.1134/S1062739121030170
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Optimization and Analysis of Drilling and Blasting Parameters Using O-Pitblast Software
The development of modern technologies has enabled the application of specialized softwares in the field of mining through various segments and processes, including in works related to drilling and blasting. The application of specialized software for drilling and blasting with the use of modern technologies such as photogrammetry enabled more accurate data from the field for later processing. By processing data and creating a 3D model of the terrain for drilling and blasting works, it can obtain precise data, ...Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić. "Optimization and Analysis of Drilling and Blasting Parameters Using O-Pitblast Software" in Podzemni radovi, Beograd : Rudarsko-geološki fakultet (2024)
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Risk Evaluation: Brief Review and Innovation Model Based on Fuzzy Logic and MCDM
Stevan Djenadic, Milos Tanasijevic, Predrag Jovancic, Dragan Ignjatovic, Dejan Petrovic, Ugljesa Bugaric (2022)The risk assessment of engineering systems represents an important part of the quality of service and dependability. The existing methods for risk evaluation use crisp sets for rating partial indicators’ proposition and their cumulative products as an overall indicator. In this paper, existing FMEA and FMECA methods have been improved using the fuzzy expert system for calculating the risk priority number. The application of fuzzy logic allows the use of linguistic descriptions for risk analysis. In this way, the ...Stevan Djenadic, Milos Tanasijevic, Predrag Jovancic, Dragan Ignjatovic, Dejan Petrovic, Ugljesa Bugaric. "Risk Evaluation: Brief Review and Innovation Model Based on Fuzzy Logic and MCDM" in Mathematics, MDPI AG (2022). https://doi.org/10.3390/math10050811
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Design of the Opencast Coal Mine Drmno Dewatering System
Development of mining in the opencast mine Drmno from Kostolac basin in Serbia is carried out in the increasingly complex geological and hydro geological conditions with the decline of the coal seams to the alluvial part of Europe's largest river Danube. Greater depth and inflow of groundwater significantly increase costs for dewatering facilities construction with the requirement for optimizing of this more and more important surface mining process. Making decision on screen construction in the opencast mine with redesign ...dewatering system, groundwater, hydrodynamic model, dewatering wells, screen, reliability, environmental effects.Vladimir Pavlović, Dušan Polomčić, Tomislav Šubaranović. "Design of the Opencast Coal Mine Drmno Dewatering System" in Proceedings of the 12th International Symposium Continuous Surface Mining - Aachen 2014, Springer International Publishing (2014). https://doi.org/10.1007/978-3-319-12301-1_11
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Substitution reactions of some novel sterically hindered monofunctional Pd(II) complexes
Reakcije supstitucije monofunkcionalnih kompleksa [(TLtBu)PdCl]+ i [Pd(tpdm)Cl]+, gde je TLtBu = 2,6-bis[(1,3-di-terc-butilimidazolin-2-imino)metil]piridin i tpdm = terpiridindimetan, sa nukleofilima kao što su: tiourea, I−, Br−, NO2−, piridin i dimetil-sulfoksid (DMSO) proučavani su u 0,1 M vodenom rastvoru NaClO4 u prisustvu 10 mM NaCl. Reakcije su sprovedene na tri različite temperature (288, 298 i 308 K) korišćenjem tehnike zaustavljenog protoka na različitim temperaturama. Reakcije supstitucije su praćene pod uslovima pseudo prvog reda sa velikim viškom nukleofila. Dobijeni rezultati pokazuju da kompleks ...... these complexes are novel, for better understanding of their characteristics we compared the rate con- stants for the substitution reactions with I� with earlier published values for some other sterically crowded monofunctional Pd(II) complexes, Table 2. According to the values for the second-order rate constant ...
... spontaneous hydrolysis of the complexes. The temperature dependence of the second-order rate con- stants was studied for the reactions of [(TLtBu)PdCl]+ complex with I� and pyridine and for the [Pd(tpdm)Cl]+ complex with I�, Br�, pyridine and DMSO. The observed pseudo-first-order rate constants, kobs, ...
... spontaneous hydrolysis of the complexes. The temperature dependence of the second-order rate con- stants was studied for the reactions of [(TL®")PdCl]* complex with I- and pyridine and for the [Pd(tpdm)Cl]* complex with I-, Br-, pyridine and DMSO. The observed pseudo-first-order rate constants, kops, were ...Aleksandar Mijatović, Jovana Bogojeski, Biljana Petrović, Živadin D. Bugarčić. "Substitution reactions of some novel sterically hindered monofunctional Pd(II) complexes" in Inorganica Chimica Acta, Elsevier BV (2011). https://doi.org/10.1016/j.ica.2011.11.031
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Sentiment Analysis of Serbian Old Novels
In this paper we present first study of Sentiment Analysis (SA) of Serbian novels from the 1840-1920 period. The preparation of sentiment lexicon was based on three existing lexicons: NRC, AFFIN and Bing with additional extensive corrections. The first phase of dataset refinement included filtering the word that are not found in Serbian morphological dictionary and in second automatic POS tagging and lemma were manually corrected. The polarity lexicon was extracted and transformed into ontolex-lemon and published as initial ...Ranka Stanković, Miloš Košprdić, Milica Ikonić Nešić, Tijana Radović. "Sentiment Analysis of Serbian Old Novels" in Proceedings of the 2nd Workshop on Sentiment Analysis and Linguistic Linked Data, June 2022, Marseille, France, European Language Resources Association (2022)
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Development of the Cost-Based Model for Monitoring the Lifetime of the Earth Moving Machines
This paper presents the model for the identification of reference points on the lifetime curve of engineering systems. This curve commonly represents the increase and decline of failure in relation to time. A direct correlation between failure rate and costs is assumed in this paper, therefore, statistical and empirical analysis of costs provided reference points. This approach is used for positioning stages of the engineering system’s lifetime with a minimal number of failures and costs, regardless of whether these ...Electrical and Electronic Engineering,Industrial and Manufacturing Engineering, Control and Optimization, Mechanical Engineering, Computer Science (miscellaneous), Control and Systems EngineeringUgljesa Bugarić, Milos Tanasijević, Stevan Djenadić, Dragan Ignjatović, Ivan Janković. "Development of the Cost-Based Model for Monitoring the Lifetime of the Earth Moving Machines" in Machines, MDPI AG (2022). https://doi.org/10.3390/machines10110995