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Упит dcterms_subject_txt:Fluid Flow and Transfer Processes

2429 items

  • Novi pristup proučavanju tekstura minerala značajnih za istraživanje rudnih ležišta

    Aleksandar Pačevski (2022)
    ... 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 ...
    ... 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 ...
    ... 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 ...

  • A contribution to the understanding of hydrochemical properties of thermomineral water on the L’dži locality (eastern part of North Macedonia)

    Hristina Petrova, Katarzyna Wątor, Piotr Rusiniak, Boris Vakanjac, Vesna Ristić Vakanjac, Ewa Kmiecik (2023)
    Regarding the aspect of mineral, thermo-mineral, and thermal waters, on the territory of the Republic of North Macedonia, there are 65 registered locations, of which 8 are categorized as spas. This includes the Kežovica spa, also known as the Štipska spa. In the vicinity of Kežovica Spa is the thermo-mineral L’Dži spring with mineralization around 1.3 g/L and the water temperature at the time of sampling was 50.1 °C. Spring L’Dži is generated by a fault structure and is ...
    termomineralne vode, hemizam voda, hidrohemijske karakteristike, lokalitet L’dži, Republika Severna Makedonija

  • Callovian (Middle Jurassic) Sphriganaria (Brachiopoda) from the Jordan Valley (Middle East)

    Howard R. Feldman, Barbara V. Radulović, Fayez Ahmad (2023)
    Brachiopods, Middle Jurassic, Sphriganaria, shell microstructure, Ethiopian Province

  • Ostvarivanje dobiti pri uvođenju sistema agregatnih zamena na osnovnoj rudarskoj mehanizaciji površinskih kopova EPS

    Predrag Jovančić, Ignjatović Dragan, Đenadić Stevan (2021)
    Jedan od osnovnih zadataka na površinskim kopovima uglja je ostvarivanje zadovoljavajućeg vremenskog i kapacitetnog iskorišćenja kontinualnih sistema. Da bi se to postiglo, neophodno je izvršiti izmene u postojećoj strategiji održavanja. Preduslov je uvođenje agregatne zamene vitalnih delova na rudarskim mašinama. Benefiti su višestruki. Očekivani rezultati ovakvog pristupa su: smanjenje zastoja i povećanje vremena rada; direktne materijalne uštede; bolja organizacija rada; racionalizaciju radioničkih i magacinskih kapaciteta; povećanje vrednosti mašina. Da bi se uvela agregatna zamena neophodne su investicije za nabavku ...
    agregatne zamene, održavanje, mehanizacija, Benefit Cost analiza
    ... realized for the third year from the initial investment, exceeding the investment costs. The cumulative cash flow shows that the initial investment returns in the ninth year of investment and twenty years of operation generate about 70 million euros in cash. 1 Dr Jovančić Predrag, Univerzitet ...
    ... machines. The benefits are multiple. The expected results of this approach are reducing downtime and increasing operating time; economic savings; better work organization; rationalization of workshop and warehouse capacities; increasing machines value. To introduce aggregate replacement, investments ...
    ... Asset management - Overview, principles and terminology [9] International Electrotechnical Commission. International standard - Dependability management ISO-IEC 300. http://www.iec.ch/ [10] International Electrotechnical Vocabulary, Dependability and Quality of service, IEC Standard 50(191) ...

  • 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 ...
    Ceria, Yttrium, Solid solution, Mechanosynthesis, Oxygen vacancy, Nanocrystalline material

  • Prirodno prečišćavanje i stimulisana bioremedijacija podzemnih voda zagađenih naftnim ugljovodonicima

    Nenad M. Marić (2016-09-26)
    Disertacija se konceptualno sastoji iz dva dela kojima je obuhvaćen pasivan (prirodnoprečišćavanje) i aktivan remedijacioni pristup (stimulisana bioremedijacija) kodpodzemnih voda zagađenih naftnim ugljovodonicima.U prvom delu disertacije prikazani su rezultati osmatranja procesa prirodnogprečišćavanja u podzemnim vodama na lokaciji istorijskog zagađenja kerozinom.Tragovi zagađenja naftnim ugljovodonicima pronađeni su 20 godina nakon prosipanjakerozina. Ovo je stvorilo osnovu za proučavanje efekata dugotrajne izloženostipodzemnih voda procesima biodegradacije u terenskim uslovima. Uočeno je da sesnižene koncentracije elektron akceptora (O2, NO3-, SO42-) i povišene koncentracijemetaboličkih produkata biodegradacije ...
    podzemne vode, naftni ugljovodonici, kerozin, prirodno prečišćavanje,stimulisana bioremedijacija

  • Inhibitory effect of platinum and ruthenium bipyridyl complexes on porcine pancreatic phospholipase A2

    Tina Kamčeva, Jörg Flemmig, Bojana Damnjanović, Jürgen Arnhold, Aleksandar Mijatović, Marijana Petković (2011)
    Fosfolipaza pankreasa A2 (PLA2) igra važnu ulogu u ćelijskoj homeostazi kao iu procesu karcinogeneze. Efekti metalo-lekova koji se koriste kao hemoterapeutici na aktivnost ovog enzima nisu poznati. U ovom radu, interakcija između PLA2 svinjskog pankreasa i dva odabrana kompleksa prelaznih metala — tetrahloro(bipiridin) platine(IV) ([PtCl4(bipi)]) i dihloro (bipiridin) rutenijum(III)hlorida ([RuCl2(bipi)2) ]Cl)—proučavana je. Laserska desorpcija/jonizacija uz pomoć matriksa, vremenska masa spektrometrija (MALDI-TOF MS) i fluorescentna spektroskopija korišćeni su za analizu aktivnosti enzima u odsustvu i prisustvu metalnih kompleksa i za ...
    Metals and Alloys, Biochemistry, Biomaterials, Biophysics, Chemistry (miscellaneous)

  • Optimising in electrical energy consumption in mining plants

    Snežana Aleksandrović, Vesna Damnjanović, Ilija Jeftenić (2018)
    ... overview of the haracteristics. of standard and energy ecfficient motors of ifferent power and load, some common and universally pplicable results can be reached. This paper addresses the way efficiency of the entire drive depends on the motor power factor, and discusses the modes by which reactive power ...
    ... C. Khanchi and V. K. Garg, “Power Factor Improvement of Induction Motor by Using Capacitors,” Int J Eng Tr and Technol, vol.4, pp.2967- 2971,2013. ABSTRACT Optimising in clectrical energy consumption in mining, in open-pit mines, can be achieved not only by constant monitoring and analysing of ...
    ... of its flow, but by checking the ficiency of consumer Wwork, since even the most efficient upply represents a loss for an unnecessary or unproductive onsumption. In mostindustries a considerable portion of ectrical energy goes to motor driven systems. One of the ajor factors of electrical energy ...

  • Chalcopyrite Floatability in Flotation Plant of the Rudnik Mine

    Predrag Lazić, Đurica Nikšić, Rudolf Tomanec, Dušica Vučinić, Lidija Cvetićanin (2020)
    У раду је приказан део резултата обимних индустријских испитивања утицаја финоће млевења руде на резултате флотације минерала олова, бакра и цинка из руде рудника "Рудник". На основу резултата индустријских испитивања, констатовано је да се при једностепеном млевењу и двостепеном класирању комплексне Pb-Zn-Cu руде, појављује проблем тзв. диференцијалне мељивости. Наиме, галенит као мек минерал знатно брже се уситњава од осталих минерала у руди. Ово доводи до тога да минерал галенит прелази у ситне класе које споро флотају, а у ...
    флотабилност халкопирита, диференцијална мељивост, флотација, рудник
    ... 1. SAMPLES AND METHODS Research samples in all three series (traditional, coarse and fine milling) were taken in flotation plant of the Rudnik mine (Fig. 1). Lead underflow samples 7 were taken on copper flotation cycle conditioning entering, by stream notch of the pulp flow to conditioning ...
    ... selectivity between copper and zinc minerals. Only 20% of chalcopyrite is in fractions which are suitable to flotation (in range 18—74 nm). Ore specimen 31 (coarse fractions). Chalcopyrite is the most present mineral and pyrrhotite, marmatite and galena follow. Cubanite, vallerite and covellite are present ...
    ... L., Mainza, N., Becker, M., and Wiese, G., Using Mineralogical and Particle Shape Analysis to Investigate Enhanced Mineral Liberation through Phase Boundary Fracture, Powder Techmology, 2016, no. 301, pp. 794—804. 6. Venkataraman, S. and Fuerstenau, F., Kinetic and Energy Considerations in Mixture ...

  • Indexing of textual databases based on lexical resources: A case study for Serbian

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2015)
    In this paper we describe an approach to improvement of information retrieval results for large textual databases by pre-indexing documents using bag-of-words and Named Entity Recognition. The approach was applied on a database of geological projects financed by the Republic of Serbia in the last half century. Each document within this database is described by metadata, consisting of several fields such as title, domain, keywords, abstract, geographical location and the like. A bag of words was produced from these ...

  • Optimizacija utovarno-transportnih sistema u funkciji planiranja površinskog kopa

    Mirjana V. Banković (2018-07-13)
    Profitabilna eksploatacija sve složenijih ležišta je težak zadatak koji zavisi odtemeljnog procesa analize, planiranja i projektovanja rudnika. Izvodljiv strateškiplan mora da zadovoljava društvena, regulatorna, tehnološka, geometrijska iekonomska ograničenja. Kako bi se postigao osnovni cilj, odnosno profitabilnost iodrživost rudarskog projekta na duži period, neophodno je unapređenjematematičkih modela i informatičke podrške procesima planiranja i optimizacijekoji će omogućiti efikasnu realizaciju ovih ciljeva...
    tehnološki model, integralni model, planiranje, optimizacija,utovarno-transportni sistem, neto sadašnja vrednost projekta

  • The Nooj System as Module within an Integrated Language Processing Environment

    Ranka Stanković, Duško Vitas, Cvetana Krstev (2008)
    NooJ, electronic dictionary, lexical resources

  • Alpine thermal events in the central Serbo-Macedonian Massif (southeastern Serbia)

    Milorad D. Antić, Alexandre Kounov, Branislav Trivić, Andreas Wetzel, Irena Peytcheva, Albrecht von Quadt (2015)
    General Earth and Planetary Sciences

  • Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept

    Uroš Đurić, Miloš Marjanović, Zoran Radić, Biljana Abolmasov (2019)
    Improvements of Machine Learning-based landslide prediction models can be made by optimizing scale, customizing training samples to provide sets with the best examples, feature selection, etc. Herein, a novel approach, named Cross-Scaling, is proposed that includes the mixing of training and testing set resolutions. Hypothetically, training on a coarser resolution dataset and testing the model on a finer resolution should help the algorithm to better generalize ambiguous examples of landslide classes and yield fewer over/underestimations in the model. This ...
    klizišta, podložnost, mašinsko učenje
    ... first to implement a combination of SVM and Fuzzy approaches for debris flow modelling, and preferred SVM over the other methods. Yilmaz (2009) compared four methods for LSA (Conditional Probability, Logistic Regression, Artificial Neural Networks and SVM) using ten predictors in the Koyulhisar case study ...
    ... org/10.1023/ A:1010933404324. Cama, M., Conoscenti, C., Lombardo, L., Rotigliano, E., 2016. Exploring relationships between grid cell size and accuracy for debris-flow susceptibility models: a test in the Giampilieri catchment (Sicily, Italy). Environ. Earth Sci. https://doi.org/10.1007/ s12665-015-5047-6 ...
    ... was implemented as follows: training on 50 and testing on 25, training on 100 and testing on 25, training on 100 and testing on 50, training on 200 and testing on 25, training on 200 and testing on 50, and finally, training on 200 and testing on 100 m resolution datasets. The results clearly show that ...

  • Influence of paleoenvironmental conditions on distribution and relative abundance of saturated and aromatic hydrocarbons in sediments from the NW part of the Toplica basin, Serbia

    Nikola Burazer, Aleksandra Šajnović, Nebojša Vasić, Milica Kašanin-Grubin, Dragana Životić, João Graciano Mendonça Filho, Predrag Vulić, Branimir Jovančićević (2020)
    Stratigraphy,Economic Geology,Geology,Geophysics,Oceanography
    ... LiF200, LiF220), and two detectors (flow proportional counter - FPC and scintillation detector - SC). The instrument was able to detect all elements from Be to Am. Still, for the purpose of semi-quantitative analysis, only the measurements of Na and heavier elements were considered (O and C concentrations ...
    ... influenced by paleo-heat flow, which may be connected with the constant influx of clastic ma- terial along the whole lithostratigraphic column (Tables 1 and 2). Overall, a steady increase in values of vitrinite reflectance with depth is noticed, particularly between 603 and 1000 m, suggesting that the ...
    ... unit, where the maturation processes are more dominant, the trend n-C27 > n-C29 > n-C31 is identical, regardless of the climate change. Even though samples BL7/ 63 and BL7/64 are deposited under different climate conditions (C- value, mineralogical composition, Tables 2 and 3), the trend n- C27 > n-C29 ...

  • 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
    ... the Velika Morava and Mlava rivers, which flow into the Danube in that area (figure 1 and 2). Itis divided into two parts by the Danube - to the south is the Kostolac Basin, and to the north ofthe Danube is the Kovin Basin (Figure 2). Geological explorations began in 1941 and continues to this day ...
    ... pits of Stari Kostolac and Ćirikovac, after that in the surface mines of Klenovnik and Cirikovac, picture 2) and are not being excavated now; 177 2. Now in the excavation phase are some parts of 1, II and III layers (I and II layers in Kovin by underwater exploitation; II and III layers in the Drmno ...
    ... 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 interests us as authors and you as ...

  • A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach

    Nikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović (2024)
    This study presents a unique model for assessing the dependability of continuous parts of combined systems in open-pit mining through the application of fuzzy logic. Continuous sub-systems as part of the combined system of coal exploitation in surface mines have the basic function of ensuring safe operation, high capacity with high reliability, and low costs. These subsystems are usually part of the thermal power plant’s coal supply system and ensure stable fuel supply. The model integrates various independent partial ...
    fuzzy logic, max-min composition, continuous part of combined system (CCS), open pit, mining, dependability

  • Optimisation of underground mine decline development system using genetic algorithm

    Zoran Gligorić, Aleksandar Ganić, Rade Tokalić, Aleksandar Milutinović (2014)

  • 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

  • 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