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Упит dcterms_subject_txt:kinematic analyses

259 items

  • Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention

    Milica Ješić, Bojan Martinović, Stefan Stančić, Miroslav Crnogorac, Dušan Danilović (2023)
    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 Injection

  • Distribution of major and trace elements in the Kovin lignite (Serbia)

    Dragana Životić, Olga Cvetković, Predrag Vulić, Ivan Gržetić, Vladimir Simić, Konstantin Ilijević, Biljana Dojčinović, Suzana Erić, Bogdan Radić, Sanja Stojadinović, Snežana Trifunović (2019)
    geochemical and mineralogical study was performed on lignite samples from the Upper Miocene Kovin deposit, hosting three coal seams. The Kovin lignite is characterized by high moisture content, medium to high ash yield, medium to high sulphur content and a relatively low gross and net calorific value. The mineralogical composition, and major and trace element contents were determined by X-ray diffraction, scanning electron microscopy with energy dispersive Xray spectroscopy (SEM-EDS) analyses, and inductively coupled plasma optical emission spectrometry (ICP-OES). ...
    General Earth and Planetary Sciences, General Environmental Science
    ... and III (Figs. 2 & 3). 3.2. Lithotypes and maceral analyses The identification of lignite lithotypes (Table 1; Figs. 2 & 3) fol­ lowed the nomenclature adopted by the ICCP (1993) and TAY­ LOR et al. (1998). Polished blocks for maceral analyses were prepared accord­ ing to ISO 7404­2 (2009) and performed ...
    ... huminite (SYKOROVA et al., 2005), liptinite (PIC­ KEL et al., 2017) and inertinite (ICCP, 2001). 3.3. Proximate and ultimate analyses The proximate and ultimate analyses of lignite samples were con­ ducted using a Vario EL III CHNS/O Elemental Analyzer, Ele­ mentar Analysensysteme GmbH, according ...
    ... g ia C ro a ti ca Geologia Croatica 72/170 Table S-II. Results of proximate and ultimate analyses of individual samples (after MITROVIĆ et al., 2017 adopted). Sample ID Coal Seam Proximate analyses War (wt.%) Wan (wt.%) Adb (wt.%) Sdb (wt.%) Vdb (wt.%) Qg daf (MJ/kg) Qn daf (MJ/kg) 2/79 II ...

  • Single and multi-phase inclusions in garnets from the Lešnica alluvion in the Internal Dinarides, Serbia

    Maja Milošević, Bojan Kostić (2021)
    ... Single and multiphase inclusions in the garnets wereexamined optically by petrographic methods followed by SEM-EDS method, applied for thechemical analyses of the individual inclusion, and LA-ICP-MS applied to determine distribution andcontent of trace elements in the host garnet. Results from SEM-EDS ...

  • 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

  • Arsenic in tape waters of the south Pannonian basin (Serbia) and arsenic risk assessment

    Petar Papić, Marina Ćuk, Maja Todorović, Jana Stojković, Bojan Hajdin, Nebojša Atanacković, Dušan Polomčić (2012)
    ... y • Experimental Procedures Sampling, Field Measurements and Laboratory Analyses Groundwater samples from water supply wells within the territory of Vojvodina were used to perform arsenic con- centration analyses as part of studies conducted by the University of Belgrade, Faculty of Mining and ...
    ... of Novi Sad [22]. Total arsenic concentrations were measured in 470 water samples from public water supply systems from 2004 to 2009. Sampling and analyses of drinking water were per- formed at the following laboratories: at the Institute of Public Health of Vojvodina (in Novi Sad), the Institute of Public ...
    ... in the raw groundwater, cumulative exposure to arsenic for most endangered cities of Vojvodina and aver- age daily dose were calculated. Chemical analyses (470 samples of groundwater) were statistically processed to assess and interpret hydrochemi- cal data and to generate a prognostic hydrochemical ...

  • The subthermal potential of karstic groundwater of Kučaj–Beljanica region in Serbia estimated by the multivariate analysis

    Ljiljana Vasić, Dragana Ž. Živojinovic, Vladana Rajaković-Ognjanović, Huang Fen, Cao Jianhua (2021)
    Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Kristalografsko proučavanje strukturne desimetrizacije granata grosularsko-andraditske izomorfne serije

    Pavle I. Tančić (2016-09-21)
    U ovoj Doktorskoj disertaciji proučavano je pet različitih zona makroskopski zonarnog grandita sa lokaliteta Meka Presedla (Kopaonik, Srbija). Pomoću hemijske i elektronske analize mikroprobe preračunati su relativno visoko homogeni sastavi zona, t.j.: Grs64±1Adr36±1Sps2 (A), Grs62±1Adr38±1Sps2 (B), Grs59±2Adr40±2Sps2 (C), Grs58±2Adr41±2Sps2 (D) i Grs58±1Adr41±1Sps2 (E). Glavne promene u sastavima izražene formulom: Ca2,93-2,97Mn0,05-0,06Mg0,00-0,01Al1,14-1,26Fe3+0,72-0,83Ti0,00-0,02Si2,97-3,02O12 ukazuju da je jedina značajnija varijacija ustanovljena samo kod Al-Fe3+ raspodela u oktaedarskom položaju. Ovakav hemijski sastav je potvrđen i sa matematičkim proračunima iz IC i Raman analiza. Urađena ...
    Macroscopically zoned grandite, chemical analysis, electron microprobe analysis, Raman, Rietveld, structure, dissymmetrization, space group

  • Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization

    Maja Todorović, Jana Štrbački, Marina Ćuk, Jakov Andrijašević, Jovana Šišović, Petar Papić (2016)

  • 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
    ... Marija Radojičić1 Biljana Lazić2 Sebastijan Kaplar3 Ranka Stanković4 Ivan Obradović5 Ján Mačutek6 Lívia Leššová7 Abstract. Basic analyses of several properties of syllables (the rank-frequency distribution, the distribution of length, and the relation between length and frequency) in ...
    ... types; syllables: 239219 tokens, 2417 types) which can be used to 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 good ...
    ... syllable frequencies and syllable length) were shortly addressed in Section 4. It must be emphasized that we have preliminary results only, as the analyses were so far performed on one language only. In future, other Slavic languages and other aspects of syllables will be investigated. As there is a ...

  • Sinteza i karakterizacija nanoprahova u CeO2-Bi2O3 sistemu

    Marija D. Prekajski (2014-04-04)
    Nanoprahovi kristalnih faza iz serije čvrstih rastvora u pseudo-binarnom sistemuCeO2-Bi2O3 sintetisani su primenom jednostavne i ekonomične samopropagirajućemetode na sobnoj temperaturi korišćenjem nitrata metala i natrijum-hidroksida kaopolaznih supstanci. Osim krajnjih članova niza, CeO2 i niskotemperaturne polimorfnemodifikacije α-Bi2O3, sintetisani su i čvrsti rastvori nominalnog sastava Ce1-xBixO2-δ,gde je x = 0,1; 0,2; 0,3; 0,4; 0,5; 0,6; 0,7; 0,8; 0,9. Rezultati proučavanja metodomrendgenske difraktometrije na polikristalnom materijalu i ramanske spektroskopskeanalize pokazali su da su sintetisani prahovi sa nižim sadržajem bizmuta (x = 0,1 ...
    nanostrukturni materijali, čvrsti rastvori, CeO2, Bi2O3, rendgenskadifraktometrija praha, Ritveldova metoda, mikrostrukrurna analiza

  • Regionalna karakterizacija karstnih podzemnih voda dela centralnog Balkana u funkciji njihovog održivog korišćenja i menadžmenta

    Veljko J. Marinović (2022)
    Karstne podzemne vode koristi oko 700 miliona ljudi na svetu, čime je njihov značaj za svetsko stanovništvo nemerljiv. U sklopu doktorske disertacije vršena su istraživanja i analize karstnih sistema dela centralnog Balkana (Srbije, Crne Gore i Savskog sliva Bosne i Hercegovine), kako bi se evaluirao ovaj dragoceni resurs. Analize su vršene na primerima karstnih sistema vrela Perućac, Seljašnica, Mokra i Mlava (Srbija), Oko Bijele i Rijeka Crnojevića (Crna Gora) i vrelo Bosne (Bosna i Hercegovina), kao i na regionalnom ...
    karstni sistem, podzemna voda, pritisci na kvantitet i kvalitet, menadžment podzemnih vodnih resursa

  • Petrological and geochemical studies of lignite from the Tamnava West field, Kolubara basin (Serbia)

    Milena Pajić, Reinhard F. Sachsenhofer, Achim Bechtel, Ksenija Stojanović, Vladimir Krstić, Dragana Životić (2021)
    ... diraD 5 2 Abstract Lignite from ihe Tamnava West held, Kolubara basin (Serbia) was investigated using micropetrography, proximate and ultimate analyses and biomarker proxy. Upper Miocene (Pontian) coal-bearmg strata consist of sandy-clayey sediments with threc coal seams. The twenty four (24) r ...

  • Hazardous substances in karst aquifer waters - one of the results of the operational monitoring of groundwater in Serbia

    Zoran Stevanović, Veljko Marinović, Branislav Petrović (2020)
    У циљу оцене стања животне средине и разумевања потенцијалних узрока још раније евидентираног лошег хемијског статуса водног тела подземних вода „Крш–север“, извршенa je хидрогеолошка проспекција шире околине лежишта бакра Мајданпек, која је укључилаистраживање површинског копа, флотационог језера и главних карстних врела и пећина. Имајући у виду да се експлоатационо поље рудника бакра Мајданпек директно граничи са карстном издани и водним телом подземних вода „Крш–север“, параметри квалитета подземне воде су анализирани (in situ и лабораторијски) на два главна карстна врела ...
    Опасне супстанце, карстна издан, бакар, флотацијско језеро, Мајданпек, Србија

  • Tracking of the temporal dependency of fading of the human footprint temperature contrast

    Stevan Đenadić, Ljubiša Tomić, Vesna Damnjanović, Darko Vasiljević, Danica Pavlović (2021)
    In certain situations, it is extremely important to determine the exact time “someone” entered or crossed the forbidden zone of a military or strategic installation, a red zone of radioactive, chemical, or biological contamination, a bank or similar structure. Standard security measures include ordinary video surveillance using cameras that operate in the visible range of the electromagnetic spectrum, as well commercial thermal imaging cameras [1, 2]. The paper presents the results of experiments that suggest another possible use of ...

  • Maceralni sastav i rang uglja Ibarskog basena

    Željana Novković, Nevena Andrić -Tomašević, Vladimir Simić, Dragana Životić (2022)
    Donjemiocenski ugljonosni Ibarski basen se nalazi u južnoj Srbiji. Intramontanski ektenzivni basen, izdužen u pravcu severozapad-jugoistok ispunjen je slatkovodnim sedimentima koji su formirani kao deo Dinarskog neogenog jezerskog sistema. Paleoreljef basena izgrađen je od paleozojskih amfibolskih škriljaca, sericit-hloritskih škriljaca, krečnjaka, mermera i metabazičnih stena, mezozojskih peščara, laporca, laporovitih krečnjaka, krečnjaka, dolomita, ofiolita i oligo-/miocenskih magmatskih stena. Tercijarne magmatske stene izgrađene su od oligocenskih dacito-andezita i neogenih kvarctlatita/riodacita i piroklastičnih stena. Miocenski sedimenti izgrađeni su od aluvijalnih breča, konglomerata, peščara, ...
    ugalj, macerali, refleksija vitrinita, Ibarski basen

  • Hydrothermal Synthesized and Alkaline Activated Carbons Prepared from Glucose and Fructose—Detailed Characterization and Testing in Heavy Metals and Methylene Blue Removal

    Sanja Krstić, Milan Kragović, Maja Pagnacco, Vladimir Dodevski, Branka Kaluđerović, Miloš Momčilović, Ivica Ristović, Marija Stojmenović (2018)
    glukoza, fruktoza, аktivni ugalj, hidrotermalni tretman, aktivacija hidroksida, teški metali, metilen plavo
    ... activation by various hydroxides, SEM analyses of samples were performed and results are presented in Figure 5a–c for glucose, and Figure 5d–f for fructose samples activated with different hydroxides. Obtained results were also compared with the results of SEM analyses of the samples (results are not shown) ...
    ... sample stage. The analysis of the scattered light was carried out by the spectrograph with a grating 900 lines/mm. The laser power was 1 mW. Elemental analyses of samples were performed on a Vario EL III C, H, N, S/O Elemental Analyzer (Elementar, Langenselbold, Germany). The amounts of C, N and H were determined ...
    ... crystalline structures of prepared carbonaceous materials, i.e., whether activation takes place in the same way on both sugars. For that reason, XRPD analyses of samples AC@G–T–N2–t–XOH and AC@F–T–N2–t–XOH were performed and the results are shown in Figure 2. – – – – – – – – – – – – – – – – hydroxides ...

  • Age and microfacies of oceanic Upper Triassic radiolarite components from the Middle Jurassic ophiolitic mélange in the Zlatibor Mountains (Inner Dinarides, Serbia) and their provenance

    Hans-Juergen Gawlick, Nevenka Đerić, Sigrid Missoni, Nikita Bragin, Milan Sudar, Divna Jovanović (2017)
    Neo-Tethys, trench-like basins, synorogenic deposition, evolving thrust belt, Triassic palaeogeography
    ... spectrum of the re-sedimented rocks (Blatt 1967; Zuffa 1980, 1985; Lewis 1984). Whereas the detailed provenance analyses of siliciclastic material is common, provenance analyses of carbonate or radiolarite clasts in conglomerates or breccias remain rare (Gawlick et al. 2008, 2009a, 2015, 2016a ...
    ... description of the incorporated clasts has to be combined with microfacies analyses (Fliigel 2004) and age dating. Carbonate and radiolarite clasts should be dated by their microfossil content, if possible. Such analyses provide the possibility of an exact reconstruction of the prove- nance area ...
    ... accompanied by compo- nent analysis provide an excellent possibility to reconstruct the geodynamic history of an evolving mountain belt. Component analyses of conglomerates, breccia layers or tur- bidite beds are a common tool in sedimentary geology. One classical approach is provenance analysis, ...

  • Anisotropic grossular–andradite garnets: Evidence of two stage skarn evolution from Rudnik, Central Serbia

    Bojan Kostić, Danica Srećković-Batoćanin, Petyo Filipov, Pavle Tančić, Kristijan Sokol (2021)
    This paper presents LA-ICP-MS data for garnets from the Rudnik skarn deposit (Serbia), which range from Grs45–58Adr40–52Alm2–3 in the core and Adr70–97Grs2–29Sps1 in the rim displaying anisotropy and zoning. In spite of wide compositional variations the garnets near the end-member of andradite (Adr > 90) are generally isotropic. Fe-rich rims exhibit LREE depletion and flat HREE pattern with weak negative Eu anomaly, including higher As and W contents. On the other side, the Fe-poorer core shows flat REE pattern ...
    grandite, garnets, skarn, Rudnik
    ... imaging was obtained for identifying inherited cores, cracks and inclusions inside zircon grain. U–Pb in-situ zircon dating and trace elements analyses of garnet were performed at the LA-ICP-MS laboratory of Geological Institute in Sofia, using New Wave UP193FX LA coupled to Perkin Elmer ICP-MS ...
    ... 205 ± 0.06 Th 3.01± 0.05 0.110 ± 0.05 2.72 ± 0.02 0.178 ± 0.06 Zr 119.8 ±1.37 13.2 ±1.33 117.2 ±1.30 11.8 ± 0.62 Table 1: Representative LA-ICP-MS analyses of major elements in garnet SN-310 from studied skarns (in wt. % oxides (EMPA), rounded to second decimal place), structural formula, calculated ...
    ... derived fluids responsible for andradite rim. The magmatic origin of sulphur was already previously confirmed by the uniform values of isotope analyses obtained for various sulphide minerals in the Rudnik skarn deposit: δS34 = +3.1 ± 0.3 ‰ for sphalerite, +3.0 ‰ for pyrrhotite, and +3.3 ± 0.6 ...

  • Assessments of effects of implementation of strategic plans for development of Belgrade District heating system

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Miodrag Grujić (2020)
    The district heating system (DHS) is one of the key elements of the Belgrade energy system. Overview of the current state and basic characteristics of the DHS are presented in this paper. The focus is on the planned development of DHS and on the analyses of effects of realization of measures and projects defined by strategic documents related to DHS which are adopted by city authorities (Development Strategy of DHS and Strategy of Belgrade Development). Two exploratory scenarios were ...
    Daljinsko grejanje, LEAP, Primarni energetski faktor, Uvozna zavisnost, CO2 emisija

  • The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)

    Marina Čokorilo Ilić, Ana Mladenović, Marina Ćuk, Igor Jemcov (2019)
    Geography, Planning and Development,Aquatic Science,Biochemistry,Water Science and Technology
    ... where groundwater seeped into the tunnel. On the basis of the conducted prospecting, 10 characteristic sampling points were selected for chemical analyses of the water. Groundwater was sampled on three occasions and a total of 25 samples from the tunnel were analyzed (in some places sampling was not ...
    ... tunnel’s structural stability were identified on the basis of the chemical composition of the groundwater sampled from the tunnel. The aggressiveness analyses were based on EU standard EN 206-1 [13], US Department of Transportation standard (CDT 2003) [14], and the Larson–Skold (LSkl) index [15,16]. 4. ...
    ... the HPP was placed offline, the pressure stabilized again and the water from the tunnel seeped into the hydrogeologic environment within that zone. Analyses indicated a potentially unstable zone, which is under constant hydraulic load. . Figure 5. (a) Changes of groundwater level at PP-3 (b) Operating ...