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Упит dcterms_subject_txt:backwater influence

324 items

  • Синтеза и карактеризација керамике на бази сфена

    Jelena R. Pantić (2015-07-10)
    Механохемијска активација стехиометријске смеше реактаната TiO2, SiO2 и CaCO3 показала се као веома успешна и једноставна метода за добијање сфена (CaTiSiO5). На основу мерења релативних густина свих синтерованих узорака установљено је да максималну густину од 93,9 % имају узорци који су активирани 30 минута и синтеровани на 1200 °С. Микроструктурном анализом, тј. анализом слика синтерованих узорака активираних 30 минута, које су добијене скенирајућом електронском микроскопијом, опажа се бимодална расподела величине зрна, са просечном величином од 3 μm, односно 5 ...
    сфен, механохемија, Ритвелдова метода, оптичка спектроскопија, микроструктурна анализа, фазна трансфоpмација, чврсти раствори
    ... In(OH)SO4. Acta Chem Scand 16: 1234-1244. Kalinkin A.M., Kalinkina E.V. and Makarov V.N. (2003) Mechanical activation of natural titanite and its influence on the mineral decomposition. Int J Miner Process. 69: 143-155. Докторска дисертација ...
    ... based ceramics. Process Appl Ceram 5: 79-84. Pantić J., Kremenović A., Došen A., Prekajski M., Stanković N., Baščarević Z., Matović B. (2013) Influence of mechanical activation on sphene based ceramic material synthesis. Ceram Inter 39: 1483-1488. Pantić J., Prekajski M., Dramićanin М., Abazović ...
    ... врхунским међународним часописима (М21) 1. Pantić, Ј.; Kremenović А.; Došen, A.; Prekajski, M.; Stanković, N.; Baščarević, Z.; Matović, B.: „Influence of mechanical activation on sphene based ceramic material synthesis”, Ceram Int 39 [1] (2013) 483-488. 2. Pantić, J.; Prekajski, M.; Dramićanin ...

  • Improving efficiency of thermal power plants through mine coal quality planning and control

    Mirjana Banković, Dejan Stevanović, Milica Pešić, Aleksandra Tomašević, Ljiljana Kolonja (2018)
    Главни циљ контроле квалитета угља у рудницима лигнита је снабдевање термоелектрана угљем чији квалитет мора да се креће унутар одређених квалитативних ограничења. Карактеристике угља могу да утичу на ефикасност, поузданост и расположивост како котла тако и јединица за контролу емисије. У овом раду аутори су презентовали интегрисану симулацију рударског процеса као нови приступ у истраживању променљивости калоричне вредности угља приликом експлоатације комплексног лежишта лигнита. Резултати таквог приступа омогућавају драгоцен увид у перформансе континуалног рударског система у смислу контроле променљивости ...
    mine planning, variability of coal quality, simulation, coal blending

  • Extensive vibrations of the belt conveyer drive electromotor of a bucket wheel excavator as a result of intesified wear-and-tear of its mount support

    Vesna Damnjanović, Predrag Jovančić, Snežana Aleksandrović (2017)

  • Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering

    Josip Išek, Lazar Kaluđerović, Nikola Vuković, Maja Milošević, Ivana Vukašinović, Zorica Tomić (2020)
    γ-spectrometry, brushite, chukhrovite, phosphogypsum, radionuclides, recrystallization
    ... 176010 and Project No. 43007. References Amjad Z. (1988) Calcium sulfate dihydrate (gypsum) scale formation on heat exchanger surfaces: the influence of scale inhibitors. Journal of Colloid and Interface Science, 123(2), 523–536. Azimi G. (2010) Evaluating the Potential of Scaling Due to Calcium ...

  • Hidrogeoekološki aspekti aksploatacije uglja u Pelagonijskom basenu (Makedonija)

    Kostadin J. Jovanov (2016-06-24)
    Leţišta uglja „Suvodol“, „Brod-Gneotino“ su u eksploataciji, a leţište uglja „Ţivojno“je u fazi pripremi. Nalaze se u krajnjem jugoistočnom i juţnom delu Pelagonijskekotline. Sva tri leţišta stvorena su u neogenim sedimentima u jezerskim uslovimasedimentacije u zoni kontakta sa prekambrijumskim kristalastim stenama. Kod sva trileţišta ugalja se javljaju više slojeva različite debljine, u okviru kojih se nalaze klastičnisedimenti (gline, peskovi i dr.). U podini ugljenog basena nalaze se kristalaste steneprekambrijumske starosti.Teren u okolini leţišta uglja karakteriše se umereno kontinentalnom klimom, ...
    ugalj, podzemne vode, površinske vode, neogeni kompleks, izdani,transmisibilnost, nivo podzemne vode, sniţenje nivoa
    ... works. Coal exploitation as well as the coal drainage works has quite an influence on the environment. Coal mines have rather an influence on the environment. The mentioned v activities have a negative influence on degradation of the natural relief and hydro geographic network, co ...
    ... their chemical composition. In some parts of the basin, typical mineral coal acidic water with high content of CO2 gas could be found. A dominant influence in the formation of mining water in existing mining works have ground waters from aquifers in sandy Neogen sediments and precipitation water which ...
    ... east. Measuring of air quality is necessary so that the environment could be protected; the level of ground and surface water in the area has an influence on the mining activities, water quality and taking certain measures during the closing, conservation of mining works and re-cultivation of terrain ...

  • The effect of finite driving rate on avalanche distributions

    Sonja Radić, Sanja Janićević, Dragutin Jovković, Đorđe Spasojević (2021)
    Statistics, Probability and Uncertainty,Statistics and Probability,Statistical and Nonlinear Physics

  • Multiple-Criteria Decision-Making in Mine Development Planning

    Sanja Bajić (2023)
    The Borska Reka ore deposit is an experimental location where developed methodologies have been applied. It is the largest ore body within the Bor mining complex, which has been the subject of numerous studies and analyses for more than three decades. The paper focuses on the application of FAHP and the VIKOR method to address ranking of alternatives and select the optimal mining method by means of fuzzy multicriteria optimization.

  • 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
    ... G eo lo g ia C ro a ti ca Geologia Croatica 72/162 (GLUSKOTER, 1975; TAYLOR et al., 1998; WARD, 2016). Epi­ genetic factors may also influence the variation in elements (CHRISTANIS et al., 1998; KALAITZIDIS et al., 2002; DAI et al., 2012). The modes of mineral occurrences, their abundance ...
    ... ited wet forest swamp. The high content of carbonate and sulphate minerals with relatively high Ca and total sulphur content (Sdb) indicate the influence of neutral to alkaline groundwater. Further­ more, a good negative correlation coefficient between Ca and ash content (Table 8; Table S­VI of the ...
    ... for Standardization, Swit­ zerland (7 p). KALAITZIDIS, S., CHRISTANIS, K., GEORGAKOPOULOS, A., FERNÁNDEZ­TU­ RIEL, J.L. & PAPAZISIMOU, S. (2002): Influence of geological conditions dur­ ing peat accumulation on trace element affinities and their behavior during peat combustion.– Energy Fuel, 16, 1476–1482 ...

  • An intelligent hybrid system for surface coal mine safety analysis

    Nikola Lilić, Ivan Obradović, Aleksandar Cvjetić (2010)

  • From DELA Based Dictionary to Leximirka Lexical Database

    Biljana Lazić, Mihailo Škorić (2020)
    In this paper, we will present an approach in transforming Serbian language Morphological dictionaries from a DELA text format to a lexical database dubbed Leximirka. Considering the benefits of storing data within a database when compared to storing them in textual documents, we will outline some of the functionality that the database has made possible. We will also show how hand-made rules that use category labels lexical entries are marked with can be used to link lexical entries. ...
    Morfološki rečnici, jezički resursi, Leksimirka
    ... es are electronic dictionaries primarily intended for machine use. This type of dictionary was first developed for the French language under the influence of linguist Maurice Gross and it is one of the first electronic dictionaries, used before the database notion. These dictionaries also exist for many ...

  • Properties of fly ash and slag from the power plants

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    This paper describes the physical, chemical and mineral properties of ash and slag, which were taken from thermal power plants Nikola Tesla A, Nikola Tesla B, Kostolac A and Kostolac B. The knowledge of the mineralogical material composition is important because the type of minerals directly determines the properties of the fly ash and slag and their possible application. Laboratory tests showed that ash and slag samples consist of the following minerals: amorphous materials, quartz, feldspar, mullite, melilite, cristobalite, ...
    fly ash, slag, physical composition, chemical composition, mineral composition, X-ray diffraction method
    ... water. The fly ash and slag landfills in Serbia occupy an area of 1639 ha and if they are under constant control and monitoring, significantly influence the dis- ruption of the environment, which is reflected in the pollution of: air, soil, surface water and groundwater, vegetation cover, as well ...

  • Development and Evaluation of Three Named Entity Recognition Systems for Serbian - The Case of Personal Names

    Branislava Šandrih, Cvetana Krstev, Ranka Stanković (2019)
    In this paper we present a rule- and lexicon-based system for the recognition of Named Entities (NE) in Serbian news paper texts that was used to prepare a gold standard annotated with personal names. It was further used to prepare training sets for four different levels of annota tion, which were further used to train two Named Entity Recognition (NER) sys tems: Stanford and spaCy. All obtained models, together with a rule- and lexicon based system were evaluated on ...
    NER, Named Entity Recognition Systems, Serbian, Personal Names
    ... news in GOLD- PERS that come from 6 different sources were pro- duced at the same time period, and thus involved same persons. However, that did not influence results favorably towards STUDENTS_GOLD test text. All measures are for all NER systems and models highest for weak calculation, followed by weighted ...

  • Crystallography and Surface Oxidation of Stoichiometric Arsenopyrite from Šumadija-Kopaonik Pb-Zn/Polymetallic Ore District (Serbia)

    Ivana Jelić, Aleksandar Pačevski, Aleksandar Kremenović, Aleš Šoster, Andreja Šestan, Janez Zavašnik (2023)
    The behaviour and stability of arsenopyrite largely depend on its crystal structure, but studies of crystallography and structural defects are scarce. For clarification, we investigated a series of natural arsenopyrite crystals from the polymetallic Pb-Zn-(±Cu,Ag,Au,Sb,Bi,W) Šumadija-Kopaonik ore district (Serbia) by powder X-ray diffraction (XRPD). Among them, samples from the Drenjak gold mineralisation showed near-stoichiometric FeAsS composition and were further investigated by conventional and high-resolution transmission electron microscopy methods. TEM revealed abundant planar crystallographic defects and epitaxial surface oxide layer ...
    Inorganic Chemistry, Condensed Matter Physics,General Materials Science, General Chemical Engineering, crystal structure, FeAsS, oxidation, TEM, XRPD
    ... 3 vol.%, while 30 nm thick oxide accounts for 1.8 vol.%, which is already enough to be detected by conventional XRPD. Therefore, the possible influence of the epitaxial superficial oxides affecting, the accurate diffraction measurements has to be considered in the diffraction data interpretation ...

  • Integrative GHG Assessment in Oil and Gas Industry

    Aleksandar Mirković, Marija Živković, Stevan Đenadić, Darja Lubarda, Chinedu Anyanwa (2023)
    Reducing greenhouse gas emissions is one of the main targets of national strategies in European countries. As a main contributor to emissions, the energy sector is recognized as the most promising to apply measures and actions aimed to decrease GHG emissions. The Oil and Gas industry as a significant contributor to global greenhouse gas emissions is facing a growing need for estimating, mitigating, and reducing the impact of their operations on the atmosphere to stay competitive in a newly ...
    energetska tranzicija, gasovi staklene baste, industrija, nafta i gas
    ... current level of 420 ppm [2, 3|. The concentrations of CO» and CHu in 2019 were the highest recorded in recent history [4]. It is assumed that human influence has led to the global retrcat of glacicrs since the 1990s and thc retreat of the surface of the Arctic Sea ice between 1979—1988 and 2010—2019 [4] ...

  • 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

  • Clockwise vertical-axis rotation in the West Vardar zone of Serbia: Tectonic implications

    Vesna Lesić, Emo Márton, Violeta Gajić, Dragana Jovanović, Vesna Cvetkov (2018)
    The Vardar-Tethyan mega-suture between the Eurasian and Adria (Gondwana) margins comprises remnants of oceanic lithosphere of Neotethys and distal parts of the adjacent continental margins including unconformable Late Cretaceous sedimentary cover and Cenozoic igneous rocks of post-obduction age. This study provides kinematic constraints for displacements and rotations affecting the Serbian part of the West Vardar and Jadar-Kopaonik units after the closure of the Neotethyan (= Sava) Ocean. The targets of the paleomagnetic research were Late Cretaceous sediments representing an ...
    Paleomagnetism, Clockwise rotation, Dinarides, West Vardar zone
    ... dacito-andesites as well as the granodiorites (Lesić et al. 2013). In this paper they will be discussed later and in the context with their possible influence on the paleomagnetic vectors. The Oligocene dacito-andesites from the Kopaonik Mts. area (Fig. 3) were thermally demagnetized. The NRM decayed ...
    ... Omitting sites, which considerably (40� or more, a limit set by Wilson et al. 1972) depart from the overall mean paleomagnetic direc- tion has little influence on the direction itself, yet improves considerably the statistical parameters. The outliers could have been affected by moderate post-emplacement ...

  • Nonequilibrium athermal random-field Ising model on hexagonal lattices

    Svetislav Mijatović, Dragutin Jovković, Đorđe Spasojević (2021)
    Изингов модел, хексагонална решетка

  • Uticaj raspadanja na stabilnost kosina u mekoj stenskoj masi

    Anđela Despotov (2024)
    U radu je opisano ponašanje mekih stenskih masa koje su izložene porecesu raspadanja tokom određenog vremenskog perioda. Meke stenske predstavljaju kritične vrste stenskih masa pošto izazivaju različite probleme tokom izvođenja građevinskih radova. Meke stene mogu biti sedimentne stene, raspadnute metamorfne i magmatske stene. Odlikuju se niskim vrednostima čvrstoće, visokom deformabilnošću, visokom plastičnošću, podložne su dezintegraciji i fizičko-hemijskom raspadanju, odnosno ubrzanom dejstvu površinskog raspadanja usled atmosferskih uticaja.Za klasifikaciju mekih stenskih masa koriste se modifikovane verzije već postojećih klasifikacionih sistema. Jedan ...
    meke stenske mase, dezintegracija, klasifikacioni sistemi, Slake durability test
    ... Experimental investigation on the influence of temperature on the mechanical properties of reservoir rocks. International Journal of Rock Mechanics and Mining Sciences, Volume 34, article id. 298.e1. 27. Sousa i dr. (1997), Experimental investigation on the influence of temperature on the mechanical ...

  • Using Metadata For Content Indexing Within An OER Network

    Ranka Stanković, Olivera Kitanović, Ivan Obradović, Roberto Linzalone, Giovanni Schiuma, Daniela Carlucci (2014)
    ... for learning, estimated duration of the course and degree of interactivity. Interactivity level indicates the degree to which the learner can influence the aspect or behaviour of the resource. Value for this field can be "very low", fora document intended for printing; "low",a video clip with ...

  • The use of biological markers in determination of origin and type of organic matter in the Tisza river sediments

    Snežana Štrbac, Gordana Gajica, Aleksandra Šajnović, Nebojša Vasić, Ksenija Stojanović, Branimir Jovančićević (2013)
    The objective of the study was to determine the origin and type of organic matter (OM) of the Tisza recent sediments along the distance of 153 km through the territory of Serbia. For this purpose group organic-geochemical parameters and biomarker compositions were used. All samples contain approximately same amount of OM, which was deposited under uniform, slightly reducing conditions. Based on the distribution of n-alkanes, the origin and type of OM could not be precisely estimated. However, n-alkane patterns ...
    sediments, Tisza River, organic matter, biomarkers, oil pollutants
    ... ratios are in a range typical for crude oils (Table VI).1 The slightly lower values of these parameters than in crude oils could be attributed to the influence of singenetic immature terrestrial organic matter (expressed through an elevated concentration of C2914α(H)17α(H)20(R)-sterane), the presence of ...