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Упит dcterms_subject_txt:Physical and Theoretical Chemistry

2342 items

  • Identification of the Best Available Renewable Energy Source for Electricity Production in Serbia

    Boban Pavlović, Dejan Ivezić, Marija Živković (2020)
    Around 2/3 of electricity production in Serbia originates from coal-fired thermal power plants. The most significant domestic coal deposits are lignite deposits, a type of low -quality coal that causes negative health, climate and environmental impacts during the combustion. To reduce those negative impacts on domestic electricity production and to promote environmental awareness, the Serbian Energy Sector Development Strategy and the National Action Plan for Use of Renewable Energy Sources indicate the plan for increasing the share of ...
    Strategija obnovljive energije, Održiva energija, Proizvodnja električne energije, Solarna energija, Biomasa, Hidroenergije, Energija vetra
    ... experts' judgments and availa ble literature. The results of th e FAHP reveal that biom ass has the highest rank among the RES to generate electricity and a s su ch can be characterized as a strategic RES. Wind and hydro energy are ranked second and th ird, respectively, and solar is in the last ...
    ... approach th at consists of econom ic, environmental, technical, and socio-political criteria. Further on, the Fu zzy A nalytical Hierarchy Pr ocess (FA HP) m ethod is u sed for a ssessing four renewables (biom ass, hydro, solar and wind) in regard to the defined criteria. The obtained weights for ...
    ... Source for Electricity Production in Serbia | Boban Pavlović, Dejan Ivezić, Marija Živković | Conference on Sustainable Development of Energy, Water and Environment Systems, Sarajevo, 28.6.-2.7.2020. | 2020 | | http://dr.rgf.bg.ac.rs/s/repo/item/0005061 Дигитални репозиторијум Рударско-геолошког факултета ...

  • Uniaxial compressive strength test before and after standard fire test on rock mass

    Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović (2022)
    ... determined experimentally. It depends on the structure of the rock mass, grain size and orientation, number and arrangement of cracks and fissures. For the same rock, strength may be different, depending on physical characteristics. Heat of environment can affect structure of rock mass, which results ...
    ... fragments of rock minerals and mica (muscovite and chlorite) which are bound with a limonite clay cement. Quartz clusters dominate, building about 60% of the rock mass. They occur in grains of different sizes, from 0.05 to 0.5 mm. The grains are mostly sub-rounded and partly un-rounded. Some have ...
    ... existence of primary and secondary tunnel structure, the rock itself will not develop as high temperatures in case of fire, as they were in standard fire test. REFERENCES Hoek, E. and Brown, E.T., 1980. Underground excavations in rock. The Institution of Mining and Metallurgy, London ...

  • Mafic alkaline metasomatism in the lithosphere underneath East Serbia: Evidence from the study of xenoliths and the host alkali basalts

    Cvetković Vladica, Downes Hilary, Höck Volker, Prelević Dejan, Lazarov Marina (2010)
    Effects of mafic alkaline metasomatism have been investigated by a combined study of the East Serbian mantle xenoliths and their host alkaline rocks. Fertile xenoliths and tiny mineral assemblages found in depleted xenoliths have been investigated. Fertile lithologies are represented by clinopyroxene (cpx)-rich lherzolite and spinel (sp)-rich olivine websterite containing Ti–Al-rich Cr-augite, Fe-rich olivine, Fe–Al-rich orthopyroxene and Al-rich spinel. Depleted xenoliths, which are the predominant lithology in the suite of East Serbian xenoliths, are harzburgite, cpx-poor lherzolite and rare ...

  • Hydrographic and hydrological characterization of the Vodenička and Rosomačka rivers

    Vesna Ristić Vakanjac, Marina Čokorilo Ilić, Dušan Polomčić, Dragoljub Bajić, Jelena Ratković (2017)
    The Visočica River rises in Bulgaria, on the Berovo Mountain. Its course in Bulgaria is 16.7 km long. It enters Serbia near the village of Donji Krivodol. Up to the village of Pakleštica, or the beginning of Lake Zavoj, its right-bank tributaries are the Krivodolštica, the Vodenička, the Rosomačka and the Dojkinačka. There are no left-bank tributaries. Among the tributaries, water levels and discharges are gauged only on the Dojkinačka River. The Vodenička had also been gauged but only ...
    hydrographic characteristics, river discharge, the Vodenička River, the Kamenička River
    ... the Rosomačka and the Vodenička are located in southeastern Serbia, within the southern part of Mt. Stara Planina, between latitudes 43 о 07' 16'' and 43 о 13' 41'' N and longitudes 22 о 51' 0'' and 23 о 0' 43'' E. There are two villages each in the two catchments: Rosomač and Slavinja in ...
    ... Ržana and Izatovac. The only remaining station is at Braćevci. For their own needs, Pirot HPP activated the station at Pakleštica in 1990 and at Visočka Ržana in 2011. Based on available data, the paper presents a preliminary assessment of annual and monthly discharges of the Rosomačka and the Vodenička ...
    ... the villages and the number of residents smaller. The study areas are connected by a paved road (221), which links the cities of Dimitrovgrad and Pirot via Radejna, Smilovci, Izatovci, Braćevci, Slavinja, Visočka Ržana and Rsovac. Local roads are used to reach Kamenica, Senokos and Rosomač. ...

  • Combining Heterogeneous Lexical Resources

    Cvetana Krstev, Duško Vitas, Ranka Stanković, Ivan Obradović, Gordana Pavlović-Lažetić (2004)
    development of lexical resources, morphological dictionaries, WordNet
    ... already been attached to simple word entries in Serbian MD, such as +Hum (human) and +Bot (botanic) for nouns, and +Col (colour) and +Mat (material) for adjectives. The use of wordnet enables a more systematic and more detailed attachment of such marks. Moreover, the attachment can be modeled ...
    ... both (brow:1, forehead:1) and (cello:1, violoncello:1). By adding the information obtained from the WN hypernym/hyponym relations these two entries can be distinguished: for instance, cyelo,N300+BodyPart and cyelo,N300+Artifact, or cyelo,N300+Thing+BodyPart+Feature and cyelo,N300+Artifact+Devi ...
    ... language and Microsoft .Net were chosen as the basic development tools. Visual Studio .NET is a complete set of development tools for building ASP Web applications, XML Web services, desktop applications, and mobile applications. Visual Basic .NET, Visual C++ .NET, Visual C# .NET, and Visual J# ...

  • Clockwise rotation in the Serbian segment of the Vardar zone and in the Danubicum of Eastern Serbia - tetonic implication

    Vesna Lesić, Emo Marton, Vesna Cvetkov, Dragana Tomić (2015)

  • Influence of Ag doping on the morphological and magnetic properties in CuO nanopowders

    Maria Čebela, Uroš Čakar, Vesna Lojpur, Maja Milošević, Sanja Krstić, Vladimir Dodevski, Milena Rosić (2023)
    ... Serbia “Department of Mineralogy, Crystallography, Petrology and Geochemistry, Faculty of Mining and Geology, University of Belgrade, Đušina 7, 11000 Belgrade, Serbia We studied the influence of Ag doping on the crystal structure and magnetic properties of CuO nanopowders. For the synthesis of ...
    ... morphological and magnetic properties in CuO nanopowders Maria Čebela, Uroš Čakar, Vesna Lojpur, Maja Milošević, Sanja Krstić, Vladimir Dodevski, Milena Rosić Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Influence of Ag doping on the morphological and magnetic ...
    ... Serbia For Publisher Dr Dragica Stanković Printing layout Dr. Jelena Maletaškić, Vladimir V. Srdić Press Faculty of Technology and Metalurgy, Research and Development Centre of Printing Technology, Karnegieva 4, Belgrade, Serbia Published: 2023 Circulation: 120 copies CIP – Karanorusanuuja ...

  • Adsorption and Polymerization of Aniline on Cu(II)-Montmorillonite:  Vibrational Spectroscopy and ab Initio Calculation

    M. Ilić, E. Koglin, A. Pohlmeier, H. D. Narres, M. J. Schwuger (2000)
    Batch adsorption experiments in the presence of oxygen were performed to study the interlayer reactions of aniline on Cu(II)-montmorillonite in aqueous solutions. At concentrations below a critical value of CC ) 2.6 mmol dm-3 only a colored Cu(II)-aniline complex is formed, characterized by a stability constant of log(Kassoc/dm3 mol-1) ) 1.5. At concentrations beyond Cc aniline polymerizes yielding a dark brown product, which is identified by two vibrational spectroscopy techniques, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and ...
    Анилин, адсорпција, полимеризација, Cu(II)-Монтморилонит, ФТИР, аб инитио прорачун

  • Assessment of spa mineral water quality from Vrnjačka Banja, Serbia: geochemical, bacteriological, and health risk aspects

    Nebojša Đ. Pantelić, Simona Jaćimović, Jana Štrbački, Danijela B. Milovanović, Biljana P. Dojčinović, Aleksandar Ž. Kostić (2019)
    The goal of this study is to evaluate the quality of seven natural mineral water sources in the Vrnjačka Banja area used in the treatment of various diseases. The 24 macro- and microelements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The results show that element content was within allowed limits of concentration, except for B, As, and Se. The evaluated content of these elements can be associated with geological and anthropogenic factors. The sample S6 contains ...
    Management, Monitoring, Policy and Law, Pollution, General Environmental Science, General Medicine

  • A WordNet Ontology in Improving Searches of Digital Dialect Dictionary

    Miljana Mladenović, Ranka Stanković, Cvetana Krstev (2017)
    In this paper, we present a method for automatic generation of a digital resource, which connects all indirect synonyms of a dialect term to all indirect synonyms of a corresponding term in the standard language, aiming to improve the search of a digital dialect dictionary. The method uses SWRL rules defined in the Serbian WordNet ontology to identify sets of synonymous words. It also uses e-dictionaries to produce correct lemmas in standard language that users usually employ in searches. ...
    ... standard language that users usually use for search. The method was applied and evaluated on verbs and a group of nouns derived from verbs (verbal nouns). We compared results obtained by the system with those produced by humans and achieved the accuracy of 89.7%. Keywords: dialect dictionary, ontology ...
    ... ion and presenting of linguistic dialectal maps [12], [11], the analysis of the geo- graphical distribution of a language and geographical information relevant for linguistic research [9], using of Semantic Web-based techniques for representing digital resources as knowledge based resources and as Linked ...
    ... dialect dictionary data [7], or it can be one of a machine- readable and interoperable Semantic Web standards, such as RDF, SKOS and SKOS-XL which are used, for example, in the case of the dialect dictionary of the German language [15] and two Austrian dialectal dictionaries [2]. When it comes to search ...

  • Punctuated, episodic magmatism and mineralization of the Rogozna skarn-hosted Au-Zn-Pb-Cu deposits revealed through high-precision U-Pb zircon geochronology

    Sean P. Gaynor, Milorad D. Antić, Vladica Cvetković, Kristina Šarić, Urs Schaltegger (2023)
    The subvolcanic regions of magmatic centers are commonly associated with alteration, mineralization, and economic ore deposits, however the duration and frequency of mineralizing pulses within the overall lifespan of these centers can be poorly defined. Therefore, models for the formation of mineral systems require more highprecision geochronology data to refine their evolutionary models. Rogozna Mountain and its eponymous magmatic complex, located in SW Serbia, hosts multiple base metal deposits associated with variable rock types and structural expressions and serves as a natural laboratory to ...
    Skarnovska mineralizacija, Magmatsko-hidrothermalni sistemi, Subvulcanske intruzije, geohronologija na cirkonima, CA-ID-TIMS

  • Reconstruction of the Tethys' waning in the Balkans: New insights from Upper Cretaceous igneous formations and zircon provenance data

    Dejan Prelević, Kristijan Sokol, Ana Mladenović, Violeta Gajić, Vladica Cvetković (2024)
    geochronology, zircon, provenance
    ... Gondwana-related blocks and Europe, characterized by a system of pull-apart basins and transtensional tectonics. CRETACEOUS IGNEOUS FORMATIONS Upper Cretaceous igncous formations are found on both sides of the Sava-Vardar suture zone, in the Dinarides (Gondwana) and thc Serbian- Macedonian ...
    ... from both the Dinarides and Europe contain ubiquitous Neoproterozoic (Cadomian) and well-defined Silurian-Ordovician (+Devonian) populations. Carboniferous (Hercynian) zircons (>300 Ma) are predominant on the Europcan side, whereas they are considerably less intense and somewhat younger (+~300 ...
    ... differences in the provenance and age distributions. between the Dinarides . and European basement units, highlighting the distinct geological histories of these regions. The presence of Permotriassic zircons in thc Upper Cretaceous sediments of the Sava-Vardar Zone and thcir absence further cast ...

  • Waste rocks and medieval slag as sources of environmental pollution in the area of the Pb-Zn Mine Rudnik (Serbia)

    Alena Zdravković, Vladica Cvetković, Kristina Šarić, Aleksandar Pačevski, Aleksandra Rosić, Suzana Erić (2020)
    The new geochemical and mineralogical data of soil and water from the Pb-Zn Rudnik Mine area (central Serbia) reveal that the areas close to the mining sites and those located remotely from them are both affected by significant pollution by toxic elements, especially As, Pb, Ni and Cr. We, therefore, propose that two main sources are generally responsible for the current state of pollution in this area. The first is the material from waste rock dumps (WRDs) in which ...
    распадање сулфида, микроелементи, пиротин, загађење земљишта, Рударска активност, распадање шљаке

  • The number of unimodular roots of some reciprocal polynomials

    Dragan Stankov (2020)
    We introduce a sequence P2n of monic reciprocal polynomials with integer coefficients having the central coefficients fixed. We prove that the ratio between number of nonunimodular roots of P2n and its degree d has a limit when d tends to infinity. We present an algorithm for calculation the limit and a numerical method for its approximation. If P2n is the sum of a fixed number of monomials we determine the central coefficients such that the ratio has the minimal limit. ...
    Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomials

  • Long-term rockslope monitoring and rockfall prediction

    Miloš Marjanović, Biljana Abolmasov, Marko Pejić, Jelka Krušić (2021)

  • Novi pristup proučavanju tekstura minerala značajnih za istraživanje rudnih ležišta

    Aleksandar Pačevski (2022)
    ... enabled a further shift in the study of minerals and their textures to nanometer and even atomic levels, which certainly offers great opportunities, but at the mean time makes a research very complex. Scanning and Transmission Electron Microscopy (SEM and TEM) methods in combination with Electron Microprobe ...
    ... Mining and Geology, Belgrade, Serbia, E-mail: aleksandar.pacevski(ergf.bg.ac.rs Key words: texture, ore, microanalysis, pyrite The complete determination of a mineral composition and textural characteristics of the ores is crucial for correct interpretation of the ore-forming processes and genesis ...
    ... on a micrometer scale, and thus provide significantly more data important for investigating not only deposit genesis, but also possibilities and efficiency of their exploitation. With the development of polarized light microscopy as the basic methods of minerals, ores and rocks study, numerous textural ...

  • Projected changes in air temperature, precipitation and aridity in Serbia in the 21st century

    Boško Milovanović, Sebastian Schubert, Milan Radovanović, Vesna Ristić Vakanjac, Christoph Schneider (2021)
    У овој студији се испитују пројектоване промене средњих месечних и годишњих температура ваздуха, количине падавина и Де Мартоновог индекса аридности у Србији у 21. веку. У ту сврху статистички је моделована просторна дистрибуција температуре ваздуха и количине падавина на основу података 64 климатолошке станице и 421 падавинске станице за период 1976–2005 применом вишеструке линеарне регресије. Де Мартонов индекс аридности се израчунава из просторно распоређених података. Да бисмо добили регионалне просеке и варијабилност, Србију делимо на три поддомена: западну зону ...
    21 век, температуре ваздуха, климатске промене, Де Мартонеов индекс аридности, падавине, Србија

  • Dynamic and Static Elastic Properties - Laboratory Investigations of Metamorphites of the "Vranjska Banja" Series

    Jelena Majstorović, Bojan Dimitrijević, Suzana Lutovac, Snežana Savković, Miloš Gligorić (2021)
    Metamorphites of the series “Vranjska banja” built predominantly of high crystallinity schist series, alternately layered double mica, gneiss, leptonite and micaschist. For the construction of the “Prvonek” dam were carried out laboratory investigations of dynamic and static elastic properties on micashist and gneiss samples in the perpendicular and parallel direction to the foliation. These investigations provided monitoring of the rock mass anisotropy properties and greater reliability of the design parameteres. As the design of mining and construction facilities becomes ...
    micashist, gneiss, foliation, dynamic properties, static properties

  • Micro- to nanoscale textures of gold in arsenopyrite and scorodite from the As-Au-Bi assemblage of Drenjak locality (Serbia)

    Ivana Jelić, Janez Zavašnik, Marina Lazarov, Alena Zdravković, Sabina Kovač, Jovica Stojanović, Aleksandar Pačevski (2023)
    Arsenopyrite and pyrite are important carriers of Au that is present in the form of microscopic and “invisible” gold. Such gold can be expected to be released upon the process of oxidation of these sulfides. In studied gold mineralization at Drenjak, related to the granitoids of the Oligocene-Miocene Kopaonik Ore District, the main arsenopyrite-pyrite-(bismuthinite) sulfide assemblage was formed in the quartz bodies and partly replaced by scorodite (FeAsO4·2H2O) and Bi-arsenate. With only up to 5 ppm of gold recorded ...
    Economic Geology, Geochemistry and Petrology, Geology

  • Transboundary groundwater resources of Serbia - present status and future needs for sustainable management

    Veljko Marinović, Branislav Petrović, Zoran Stevanović (2021)
    Republic of Serbia is located at the crossroads of Southeast and Central Europe and belongs to the Central Balkans. With its 88,360 km2, Serbia is one of the larger countries of the Balkan Peninsula. It borders 8 countries and has at least one transboundary aquifer (TBA) with each of them. According to evaluation conducted for UNECE in 2008, Serbia has a total of 17 TBAs, out of which 15 are shared with one neighboring country, while two aquifers are shared with two or three ...
    međugranične izdani, Srbija, monitoring podzemnih voda, upravljanje podzemnim vodama