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Упит dcterms_subject_txt:scenarios of development

2853 items

  • Microstructural and magnetic properties of electrospun hematite/cuprospinel composites

    Mira Ristić, Aleksandar Kremenović, Michael Reissner, Željka Petrović, Svetozar Musić (2020)
    Phase composition, microstructural and magnetic properties of electrospun hematite/cuprospinel composites were investigated. Samples were synthesized starting with 0 to 10 mol% of copper relative to iron. The round shape of reference electrospun fbres was preserved upon their heating up to 600 °C in air, whereas at 700 °C hollow substructure was additionally formed. In these reference samples the presence of hematite phase was detected by XRPD. A small amount (traces) of Fe3O4 /γ-Fe2O3 was also found, due to the ...
    Electrical and Electronic Engineering, Condensed Matter Physics, Atomic and Molecular Physics and Optics, Electronic, Optical and Magnetic Materials

  • 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 ...
    Sphene, Phase transition, Raman spectroscopy, X-ray diffraction, SEM, IR

  • 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 ...
    lignite, heavy metals, concentrations
    ... productive humus layer of the soil that are at the top of the sedimentation sequence of this area. 181 3. COMPARATIVE PRESENTATION OF THE CONTENT OF HM IN THE LIGNITE OF THE BASIN AND SELECTED EXAMPLES - SERBIA, REGION, EUROPE AND THE WORLD For easier understanding of the content of these HM, we performed ...
    ... the geochemical characteristics of coal seams and perform a comparative analysis of coal af}ectation on the 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 ...
    ... General view of the vertical distribution of Zn, Pb and Cu in the lithological suite of the Kostolac-Kovin coal-bearing basin; blue - coal, vellow — waste The conclusion is that the contents of Zn, Pb and Cu in coal are generally significantly lower than those registered in the sediments of the tailings ...

  • Actual contamination of the Danube and Sava rivers at Belgrade (2013)

    Milan Antonijević, Marija Arsović, Josef Cáslavský, Vesna Cvetković, Predrag Dabić, Mladen Franko, Gordana Ilić, Milena Ivanovic, Nevena Ivanović, Milica Kosovac, Dragana Medić, Slobodan Najdanović, Milica Nikolić, Jovana Novaković, Tatjana Radovanović, Djurdjina Ranić, Bojan Šajatović, Gorica Špijunović, Ivana Stankov, Jelena Tošović, Polonca Trebse, Olivera Vasiljević, Jan Schwarzbauer (2014)
    rečni sistemi, stanje zagađenja, organski zagađivači, teški metali, skrining analize, non-target screening
    ... Bor, University of Belgrade, Serbia, 5Laboratory for Environmental Research, University of Nova Gorica, Slovenia, 6Faculty of Science, University of Novi Sad, Serbia, 7Faculty of Science and Mathematics, University of Niš, Serbia, 8Faculty of Science and Mathematics, University of Kragujevac, Serbia ...
    ... JAN SCHWARZBAUER9* 1School of Science, University of Greenwich, England, UK, 2High Business-Technical School, Užice, Serbia, 3Faculty of Chemistry, Brno University of Technology, Czech Republic, 4Faculty of Technology and Metallurgy, Faculty of Chemistry, Faculty of Mining and Geology, Technical ...
    ... 5 mL of ethyl acetate and 5 mL of methanol and washed with 10 mL of Milli-Q water. Then 400 mL of river water was loaded under moderate flow (3 mL min-1). SPE cart- ridge was subsequently dried under vacuum for 20 min and then the hormones were eluted with 6 mL of a mixture of ethyl acetate and methanol ...

  • Correlation Between Dynamic CBR and Compaction and Bearing Capacity of Pavement Foundation Layers

    Milan Bogdanović, Snežana Bogdanović, Dragoslav Rakić, Irena Basarić Ikodinović (2024)
    This paper presents a dynamic California Bearing Ratio (CBRd) device that can be used on a prepared pavement foundation layer to obtain a certain parameter of the tested material in the laboratory and in situ in a direct and fast way. For the selected natural material (gravel), it is shown that the laboratory CBRd can be used to estimate the compaction and bearing capacity, because it correlates well with the parameters of the standard and modifed Proctor compaction tests. ...
    korelacija parametara, donji slojevi saobraćajnica, laboratorijska i terenska ispitivanja, dinamički kalifornijski indeks nosivosti CBRd
    ... testing of the CBR+p, modulus of deformation (E,, —E,), and dynamic modulus of deformation (Ey„). The objective of regression analysis was to determine the parameters in the least-square error models, which are used to predict the conventional parameters of compaction and the bearing capacity of the ...
    ... (9) The modulus of deformation values, E,„ and E,,, were obtained without major deviations within the range of approximately 535-75 MN/m. As can be seen, the values of the modulus of deformation E,, are with- in the wide range of 90-200 MN/m?, which indicates the diversity of the material's local ...
    ... on into the substrate layer; – the method of using a non-standardized dynamic California Bearing Ratio (CBR,) device and the defi- nitions of its values under laboratory and field conditions are proposed; – the values of the modulus of deformation of the pavement foundation layer (subgrade) were ...

  • Geodynamics of basins above subducted slabs: An integrated modelling study of tectonics, sedimentation, and magmatism in the Timok Magmatic Complex

    Uros Stojadinovic, Marinko Toljic, Branislav Trivic, Radoje Pantovic, Danica Sreckovic-Batocanin, Nemanja Krstekanic, Bojan Kostic, Milos Velojic, Jelena Stefanovic, Nikola Randjelovic, Maja Males (2024)
    Timok Magmatic Complex, Neotethys subduction, basin geodynamics, analogue modelling

  • Influence of DEM resolution on numerical modelling of debris flows in RAMMS - Selanac case study

    Jelka Krušić, Biljana Abolmasov, Mileva Samardžić Petrović (2019)
    Debris flows induced by intensive rainfall represent very hazardous phenomena in many parts of the World. Methods for prediction of runout distance of flow like mass movements are different and depending on the input data, rheology, and available or appropriate numerical solution. However, sometimes it is not easy to obtain pre event and post event high-resolution data in the rural or mountainous area. Thus, the topology of terrain is the most important input parameter for the every real case ...
    tecišta, modeliranje, RAMMS, DEM
    ... Digital repository of The University of Belgrade 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 Influence of DEM resolution on numerical modelling of debris flows ...
    ... important input parameter. Resolution of DEM defines at the same time precision of curvature, and finally precision of initial parameters and deposition zones. The Selanac debris flow was triggered after extreme precipitation of about 230 mm over a period of 72 h in May 2014.The Selanac is a complex ...
    ... overflowed surface. The tangent of the effective internal friction angle of the flow material can be defined for the resistance of the solid phase (the term containing / which extensively controls deceleration behaviour of a more slowly moving flow. The resistance of the viscous or turbulent fluid ...

  • Geotechnical Conditions for Construction of Savski Trg Metro Station as a Part of the Belgrade Metro Line One

    Nemanja Stanic, Dragoslav Rakic, Josip Isek, Slavoljub Simic (2024)
    In order to solve serious traffic congestion in Belgrade, a number of studies regarding the Belgrade Metro construction have been carried out since 1973. However, only in 2019, the routes of the future metro lines 1 and 2 were de-fined as a part of the General Metro Construction Project. The lines are de-signed to intersect at the location of Sava Square, where an interchange met-ro station will be built. It represents a complex geotechnical structure consist-ing of three different ...
    metro station, geotechnical modelling, displacements

  • Upper Cretaceous scaglia type limestone from Klepa Mts. (North Macedonia) - sedimentology and biostratigraphy

    Violeta Gajić, Milena Dunčić, Ana Mladenović, Dejan Prelević (2024)
    The research area is located in the central part of North Macedonia, in the area of the Klepa Mts. Based on sedimentological, micropaleontological and biostratigraphical investigations of samples from both the east and west side of the Klepa Mts., sedimentary rocks of the Upper Creaceous age are determined. During the latest Cretaceous, this area was dominated by the sedimentation of dominantly carbonate rocks with variable amounts of clastic components. From the tectonic point of view, investigated area belongs to the ...

  • Effect of Properties of Working Fluids on the Efficiency of a Low-Temperature Organic Rankine Cycle

    Marija Živković, Aleksandar Mijatović, Dejan Ivezić, Boban Pavlović (2024)
    Decarbonization of all segments of energy systems, both on the supply and demand side, is one of the main goals of the energy transition. Electricity supply in the future will largely rely on generation from intermittent energy sources: wind and solar. Locally available, non-utilized alternative low-temperature energy sources as hydro-geothermal wells, and abounded oil and gas wells, have the potential to provide continual energy production over the year. Electricity generation from these energy sources is carried out with working ...
    svojstva, radni fluidi, efikasnost, ORC, niska temperatura

  • The Potential of Biomarkers to Distinguish Lower and Middle Miocene Lignites from the Coal-Mining District of Lusatia

    I. Kojic, J. Kus, D. Zivotic, K. Stojanovic (2021)
    ... the objective of the study is to examine the potential of biomarkers to distinguish Lower and Middle Miocene lignites in relation to sources and depositional environment of organic matter (OM). Lignite samples were collected from the 2nd Miocene Seam Horizon or its equivalent of Piskowitz (Lower ...
    ... norabietane. The hopanoid distributions of all samples dominated by C3117(H)21(H)22(R)-hopane, but Lower- and Middle Miocene lignites notably differ according to abundance of hopenes that is order of magnitude higher in later. This is associated with higher content of fernenes in Middle Miocene samples ...
    ... ratio < 0.5 (Bechtel et al., 2003) suggests a greater contribution of angiosperms. The contents of C27 and C29 n-alkanes in relation to C31 and C33 homologues imply similar impact of forested and reed-mire vegetation. The presence of tricyclic (abietane, pimarane, isopimarane) and tetracyclic (phy ...

  • A necessary and sufficient condition for an algebraic integer to be a Salem number

    Dragan Stankov (2019)
    We present a necessary and sufficient condition for a root greater than unity of a monic reciprocal polynomial of an even degree at least four, with integer coefficients, to be a Salem number. This condition requires that the minimal polynomial of some power of the algebraic integer has a linear coefficient that is relatively large. We also determine the probability that an arbitrary power of a Salem number, of certain small degrees, satisfies this condition.
    Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomials

  • Some examples of interactions between certain rare earth elements and soil

    Zlatko Nikolovski, Jelena Isailović, Dejan Jeremić, Sabina Kovač, Ilija Brčeski (2021)
    Freundlich adsorption isotherm, sequential extraction, metallic ions, ICP-OES
    ... 2Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia; 3Innovation Center of Faculty of Chemistry, University of Belgrade, Belgrade, Serbia; 4Department of Mineralogy, Crystallography, Petrology and Geochemistry, Laboratory of Crystallography, Faculty of Mining ...
    ... 11000 Belgrade, Serbia; 3Innovation Center of Faculty of Chemistry, University of Belgrade, Belgrade, Serbia; 4Department of Mineralogy, Crystallography, Petrology and Geochemistry, Laboratory of Crystallography, Faculty of Mining and Geology, University of Belgrade, Đušina 7, 11000 Belgrade, Serbia ...
    ... Preparation of soil samples for sequential extraction Dry samples of soil (sand, humus and clay type of soil, about 10 g) had previously been saturated separately with 100 ml of lanthanum (III)- ion solution concentration of 50 mg L-1 and neodymium (III)- ion solution concentration of 50 mg L-1 so ...

  • Exhumation history of the Juhor Mts. in central Serbia, the Northern Serbo–Macedonian Subunit

    Uros Stojadinovic, Hannah Pomella, Nemanja Krstekanić, Bojan Kostić, Maja Maleš, Nikola Randjelovic, Miloš Radonjić (2024)
    Northern Serbo–Macedonian Subunit, low-t thermochronology, kinematic analyses, extensional deformations

  • Frequency and Length of Syllables in Serbian

    Marija Radojičić, Biljana Lazić, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Ján Mačutek, Lívia Leššová (2019)
    Basic analyses of several properties of syllables (the rank-frequency distribution, the distribution of length, and the relation between length and frequency) in Serbian is presented. The syllabification algorithm used combines the maximum onset principle and the sonority hierarchy. Results indicate that syllables behave similarly to words as far as mathematical models are concerned, but values of parameters in models for syllables are quite different from those for words.
    frekvencije slogova, dužina slogova, srpski jezik
    ... investigate many properties of syllables. In this paper we limit ourselves to analyses of three aspects: 1) the rank-frequency distribution, 2) the distribution of length, and 3) the relation between length and frequency. The goodness-of-fit of a model is evaluated in terms of the discrepancy coefficient ...
    ... lack of its precise definition8 (cf. also Crystal, 2008, pp. 467-468; 1 Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovića 6, 21101 Novi Sad, Serbia, and Faculty of Mining and Geology, University of Belgrade, Đušina ...
    ... s.ac.rs 2 Faculty of Mining and Geology, University of Belgrade, Đušina 7, 11120 Beograd, Serbia e-mail: biljana.lazic@rgf.bg.ac.rs 3 Faculty of Technical Sciences, University of Novi Sad, Trg Dositeja Obradovića 6, 21101 Novi Sad, Serbia e-mail: kaplar@uns.ac.rs 4 Faculty of Mining and Geology ...

  • Replica of the “Great Triangle Gold Nugget” Belonging to Belgrade University Collection, Gilded or Not?

    Alena Zdravković, Maja Milošević, Ivana Jelić (2021)
    ... f.bg.ac.rs Introduction The Collection of Rocks and Minerals, Faculty of Mining and Geology, the University of Belgrade in Serbia, has been holding over a hundred years the gypsum model of triangular shape that represents the replica of one of the world’s largest native gold nugget weighing ...
    ... Collection of Rocks and Minerals, is part of old and numerous mineral collection which numbered 1525 samples donated by the St. Petersburg’s State Mining Institute of the empress Catherine II (precursor of Saint Petersburg State University) to the Mineralogical Cabinet of Great School of Belgrade ...
    ... average thickness of 8 cm, with a length of about 37 cm and height of about 27.5 cm. In order to enrich the information of gold replica as an exceptional exhibit from the 19th century and to determine its value and significance, it was important to examine the composition of its golden metallic ...

  • Underground loading-haulage equipment selection with application of topsis method with different weighting methods of criteria

    Vladimir Krivošić, Luka Crnogorac, Rade Tokalić (2024)
    The choice of adequate mining machines is one of the most complex problems in the underground exploitation of mineral raw materials. The weight of such a decision is reflected in the high prices of these machines and the occurrence of even greater costs during their use if their choice was wrongly conceived. There are numerous examples from practice in which such decisions were made solely on the basis of comparing the prices of machines, without considering any of the ...
    utovarno-transportna mehanizacija, izbor, TOPSIS, entropija, standardna devijacija, težina kriterijuma

  • Cultural Heritage and Protection of Hand-Wheeled Pottery Manufacture in Western Serbia: Characteristics of Zlakusa Pottery Based on Sem-Eds and Optical Microscopy

    Milošević Maja, Zdravković Alena, Đordjević Biljana, Jelić Ivana (2021)
    ... higher amount of calcite grains. EDS analysis gives clear differences in the chemistry of the samples. Sample 1 has a higher content of most investigated elements when compared to sample 2, except K and Ca. Amount of K and Ca elements could indicate the presence of a higher amount of illite minerals ...
    ... the obtained knowledge in the preservation of this type of cultural heritage in Serbia. Results and discussion Clay paste is a mixture of raw clays, consisted of kaolinite/halloysite, illite and smectite minerals followed with smaller amounts of quartz, feldspar and iron oxy/hydroxides ...
    ... CULTURAL HERITAGE AND PROTECTION OF HAND-WHEELED POTTERY MANUFACTURE IN WESTERN SERBIA: CHARACTERISTICS OF ZLAKUSA POTTERY BASED ON SEM-EDS AND OPTICAL MICROSCOPY MILOŠEVIĆ, M.1, ZDRAVKOVIĆ, A.1, ĐORĐEVIĆ, B.2 & JELIĆ, I.3 1Faculty of Mining and Geology, University of Belgrade, Belgrade, Serbia ...

  • Is the Sava-Vardar zone a remnant of an Upper Cretaceous ocen? Pro et contra

    Vladica Cvetković, Dejan Prelević, Ana Mladenović (2024)
    Neotethys, ocean closure, subduction
    ... CeBepHa MakcjuoHuja Fifth Congress of Geologists of thce Republic of North Macedonia IS THE SAVA-VARDAR ZONE A REMNANT OF AN UPPER CRETACEOUS OCEAN? PRO ET CONTRA !Vladica Cvetković, lDejan Prelević, ZAna Mladenović TUniversity of Belgrade, Faculty of Mining and Geology, Serbia, vladica.c ...
    ... the central Balkan Peninsula is the result of complex processes of the Neotethyan closure and the Adria(Africa)-Europe collislon. Thc exact timing of these godynamic events is closely related to the accurate understanding of the origin and evolution of the Sava-Vardar Zone (SVZ) [1]. This zone ...
    ... cvetkovic(dyrgf-bg.ac.rs TUniversity of Belgrade, Faculty of Mining and Geology, Serbia, dejan.prelević(ayrgf-bg.ac.rs TUniversity of Belgrade, Faculty of Mining and Geology, Serbia, ana.mladenovic(a)rgf-bg.ac.rs Key Words: Neotethys, occan closure, subduction INTRODUCTION The late Mesozoic geological ...

  • Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides

    Lazar Kaluđerović, Zorica Tomić, Rada Đurović-Pejčev, Maja Milošević (2021)
    ... from the environment. The efficiency of the sorption of S-metolachlor by montmorillonite depends on the size of the interlayer space, the type of interchangeable cation, and also on the characteristics of the montmorillonite surface. Disclosure of Interest: None Declared Keywords: ...
    ... CHARACTERIZATION OF NATURAL CLAY FROM BOGOVINA (SERBIA) AND POSSIBLE UTILIZATION IN SORPTION OF THE HERBICIDES Lazar M. Kaluđerović* 1, Zorica P. Tomić1, Rada Đurović-Pejčev2, Maja Milošević3 1Department for Soil Management, Faculty of Agriculture/ University of Belgrade, 2Laboratory of Chemistry, Institute ...
    ... adsorption of S-metolachlor was highest for HDTMA-montmorillonite with 1CEC saturation.  High sorption of examined herbicides on some organically modified montmorillonites creates an opportunity for application of these substrates as potentially useful material for removal of S-metolachlor ...