Претрага

Упит dcterms_subject_txt:mining technology

467 items

  • Analiza softvera za projektovanje ESP sistema

    Aleksandar Sredojević (2024)
    U momentu kada pritisak na dnu bušotine nije dovoljan da savlada ukupne gubitke pritisaka od dna bušotine do separatora, proizvodnja pomoću ležišne energije nije više moguća i bušotina prestaje sa eruptivnim radom. Kako bi ponovo omogućili proizvodnju fluida iz bušotine, potrebno je primeniti neke od mehaničkih metoda eksploatacije. Najprimenljivije mehaničke metode eksploatacije su: gas lift (GL), dubinske pumpe sa klipnim šipkama (SRP), električne uronjene centrifugalne pumpe (ESP), zavojne pumpe (PCP) i hidraulične pumpe (HP). Jadna od tih metoda koja ...
    električna centrifugalna pumpa (ESP), proizvodnja fluida, mehaničke metode eksploatacije, Prosper, Pipesim
    ... Oil and Gas Production Principls: 9th Lecture: Vertical Lift Performancee (VLP); L, Fetoui, „Productio Technology, ESP design — Step 6: Optimum Size of Compounds“, URL: Productio Technology, ESP design (30.08.2024.); Jan Dirk Jansen, (2017). „Nodal Analysis of Oil and Gas Production Systems“, ...
    ... električnih centrifugalnih pumpi“; Michael Golan, Curtis H. Whitson, (1991). „Well Performance Second Edition“, Norwegian University of science and Technology (NTNU); 76 Novičić Slobodan, (2010). „Efikasnost primene sistema potopljenih centrifugalnih pumpi na poljima NIS Naftagas-a“; Novomet, ...
    ... у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The 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 ...

  • 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

  • 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)

  • Environmental Energy Security Indicators as Tools for Environmental Protection

    Aleksandar Madžarević, Dejan Ivezić, Marija Živković , Miloš Tansijević (2019)
    Еколошка прихватљивост је постала незаменљив синтезни показатељ сваке валидне енергетске анализе у последње две-три деценије. Енергетска безбедност је у директној хармонији с еколошком прихватљивошћу кроз многе прописане политичке циљеве, економске користи, правне тековине итд. Индикатори еколошке сигурности представљају један од основних елемената за одређивање енергетске безбедности и снажне алате за усмеравање енергетског сектора ка одрживом развоју. У овом раду, анализа је била концентрисана на показатеље енергетске безбедности у области животне средине који се односе на сектор природног гаса у ...
    енергетска безбедност, еколошки енергетски индикатори, заштита животне средине, еколошка прихватљивост
    ... 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 1 7th International Symposium MINING AND ENVIRONMENTAL PROTECTION September ...
    ... 5. Ministry of Mining and Energy (2015): Strategy of Energy Development of Serbia up to 2025 with projections up to 2030, available online URL: http://www.mre.gov.rs/dokumenta-efikasnost- izvori.php (6.7.2016.) 6. Government of the Republic of Serbia, Ministry of Energy and Mining, AERS, (2005): ...
    ... emissions-from-fuel-combustion-2018-highlights 20. Henry, W.M., Knapp, K.T., Compound forms of fossil fuel fly ash emissions, Environmental Science Technology 2010, Volume 4, pp. 450-456 21. Jovašević-Stojanović, M., Bartonova, A., Current State of Particulate Matter Research and Management in Serbia ...

  • Uticaj geološke neizvesnosti u razvoju rudarskih projekata

    Petar Marković, Dejan Stevanović, Mirjana Banković (2023)
    Rudarstvo je industrija koja se nosi sa različitim vrstama neizvesnosti i rizika zbog svoje prirode i specifičnosti. Neizvesnost u rudarstvu može poticati iz različitih izvora i uticati na različite aspekte rudarskih projekata. Kao jedan od dominantnih faktora, ističe se geološka neizvesnost. Geološka neizvesnost igra ključnu ulogu u rudarstvu i može značajno uticati na procenu resursa i rezervi, planiranje eksploatacije, ekonomsku isplativost i upravljanje rizicima. Ova neizvesnost se ne može eliminisati, ali se uz primenu adekvatnih standarda i zakona može ...
    ... R. Dimitrakopoulos. (2013). Algorithmic integration of geological uncertainty in pushback designs for complex multi-process open pit mines. Mining Technology , 122 (2), 67-77. [18] Royer PS. (2000). Risk Management: The Undiscovered Dimension of Project ManagemenT. PM Network , 14, 31-40. [19] ...
    ... neizvesnost, rizik, optimizacija kopa, planiranje Abstract Mining is an industry that deals with different types of risks due to its nature and specificity. Uncertainty in mining can come from different sources and affect different aspects of mining projects. Geological uncertainty stands out as one of ...
    ... development of mining projects Petar Marković, Dejan Stevanović, Mirjana Banković Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Uticaj geološke neizvesnosti u razvoju rudarskih projekata;Impact of geological uncertainty in the development of mining projects | ...

  • 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
    ... Haxel, US Geological Survey 87 (2002) (https://pubs.usgs.gov/fs/2002/fs087-02) 14. C. Ng, J. N. Losso, W. E. Marshall, R. M. Rao, Bioresource technology 85 (2002) 131 (https://doi.org/10.1016/S0960-8524(02)00093-7) 15. S. McLeod, Notes on soil techniques (1973) 73 16. D. P. Gangwar, M. Baskar ...
    ... у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The 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 ...
    ... 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 (Received 6 October, revised 9 November, accepted 11 November 2021) Abstract: ...

  • 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
    ... Akcakoca, H., 2007, Equipment selection for high selective excavation surface coal mining. Journal of the South African Institute of Mining & Metallurgy, 107 (3), 195-210. Bag, S., Detlev, S., 2000, New technology in surface mining. Banković, M., Stevanović, D., Pešić, M., Tomašević, A.,Kolonja, L., 2017, ...
    ... selection in open pit mining: analytical hierarchy process. Istanbul University, Mining Engineering Department, 16 (2), 1-11. 193 Basçetin, A., 2004, An application of the analytic hierarchy process in equipment selection at Orhaneli open pit coal mine, Mining Technology, 113 (3), 192-199. Bascetin ...
    ... The evaluation of haulage truck size effects on open pit mining, PhD Thesis, University of British Columbia. Bozorgebrahimi, E., Hall, R., Blackwell, G., 2003, Sizing equipment for open pit mining–a review of critical parameters. Mining Technology, 112 (3), 171-179. Buhl, B., 2002, The surface mine planning ...

  • Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling

    Branislav Petrović, Veljko Marinović, Zoran Stevanović (2023)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Automatic construction of a morphological dictionary of multi-word units

    Cvetana Krstev, Ranka Stanković, Ivan Obradović, Duško Vitas, Miloš Utvić (2010)
    The development of a comprehensive morphological dictionary of multi-word units for Serbian is a very demanding task, due to the complexity of Serbian morphology. Manual production of such a dictionary proved to be extremely time-consuming. In this paper we present a procedure that automatically produces dictionary lemmas for a given list of multi-word units. To accomplish this task the procedure relies on data in e-dictionaries of Serbian simple words, which are already well developed. We also offer an evaluation ...
    electronic dictionary, Serbian, morphology, inflection, multiwordn units, noun phrases, query expansion
    ... dictionaries described in [10] and [11] that are part of the standard distribution of Unitex [12], a corpus processing system based on the finite-state technology. 4 Authors Suppressed Due to Excessive Length Table 1. Initial content of the Serbian morphological dictionary of MWUs POS lemmas forms forms/lemmas ...
    ... у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The 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 ...
    ... Cvetana Krstev1, Ranka Stanković2, Ivan Obradović2, Duško Vitas3, and Miloš Utvić1 1 Faculty of Philology, University of Belgrade 2 Faculty of Mining and Geology, University of Belgrade 3 Faculty of Mathematics, University of Belgrade Abstract. The development of a comprehensive morphological dictio- ...

  • 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
    ... n (ELRA), 2018 Tomašević, Aleksandra, Ranka Stanković, Miloš Utvić, Ivan Obradović and Božo Kolonja. “Managing mining project documentation using human lan- guage technology”. The Electronic Library Vol. 36, no. 6 (2018): 993–1009, URL https://doi.org/10.1108/EL-11-2017-0239 Vitas, Duško. ...
    ... у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The 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 ...
    ... ACCEPTED: 28 December 2019 Biljana Lazić biljana.lazic@rgf.bg.ac.rs Mihailo Škorić mihailo.skoric@rgf.bg.ac.rs University of Belgrade Faculty of Mining and Geology Belgrade, Serbia 1 Introduction Prof. Dr. Dusko Vitas and Prof. Dr. Cvetana Krstev started working on the development of Serbian mo ...

  • 2D geoelectrical resistivity tomography application at the former city waste dump "Ada Huja": Eco-geological problem

    Branislav Sretenović, Filip Arnaut, Ivana Vasiljević, Vesna Cvetkov (2019)
    2D inversion, geoelectrical method, Wenner array, ecology, Ada Huja
    ... 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 UNDERGROUND MINING ENGINEERING 34 (2019) 59-76 UDK 62 UNIVERSITY OF BELGRADE - FACULTY OF MINING AND GEOLOGY ISSN ...
    ... Branislav Sretenović1, Filip Arnaut1, Ivana Vasiljević1, Vesna Cvetkov1 Received: April 18, 2019 Accepted: June 3, 2019 Abstract: Rapid yearly technology development has enabled the possibility of renewing already acquisitioned data using new and improved software capabilities. The potential to ...
    ... (asbestos) silicates which increase the chance of 1 University of Belgrade – Faculty of Mining and Geology Emails:branislav.sretenovic@rgf.bg.ac.rs;G94-16@rgf.bg.ac.rs;ivana.vasiljevic@rgf.bg.ac.rs; vesna.cvetkov@rgf.bg.ac.rs mailto:branislav ...

  • Results of Recent Monitoring Activities on Landslide Umka, Belgrade, Serbia—IPL 181

    Biljana Abolmasov, Uroš Đurić, Jovan Popović, Marko Pejić, Mileva Samardžić Petrović, Nenad Brodić (2021)
    Klizišta, Monitoring, GNSS, Geodetska osmatranja, UAV snimci, PSInSAR
    ... University of Ljubljana Ljubljana, Slovenia Shinji Sassa Port and Airport Research Institute National Institute of Maritime, Port and Aviation Technology Yokosuka, Japan Peter T. Bobrowsky Geological Survey of Canada Sidney, BC, Canada Kaoru Takara Graduate School of Advanced Integrated Studies in ...
    ... у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The 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 ...
    ... activities are con- centrated on several landslide monitoring techniques introduced after 2014—geodetic benchmark survey B. Abolmasov (&) Faculty of Mining and Geology, University of Belgrade, Đusina 7, 11000 Belgrade, Serbia e-mail: biljana.abolmasov@rgf.bg.ac.rs U. Đurić � J. Popović � M. Pejić � ...

  • 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

  • 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

  • Geochemical evaluation of dolostone deposits in Montenegro: Implications for potential industrial applications

    Darko Bozovic, Vladimir Simic, Dragan Radulovic, Slobodan Radusinovic, Vesna Matovic, Anja Terzic (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 ...
    примарне сировине, минералогија, физичко-механичка својства, технолошка својства, наука о материјалима

  • Regulacija nivoa tečne faze u vertikalnim separatorima

    Katarina Šoštarić (2024)
    Ovaj diplomski rad bavi se regulacijom nivoa tečne faze u vertikalnim separatorima u industriji nafte i gasa. U radu su istraženi različiti metodi merenja nivoa, uključujući plovke, ultrazvučne i radarske senzore. Radarski senzori su se pokazali kao najefikasniji u teškim radnim uslovima, zahvaljujući njihovoj visokoj preciznosti i pouzdanosti. Rad uključuje teoretski pregled metoda merenja nivoa, detaljno poređenje prednosti i nedostataka različitih senzora, kao i studiju slučaja implementacije radarskog senzora u vertikalnom separatoru. Analiza rezultata i preporuke za buduća istraživanja ...
    Merenje nivoa, Vertikalni separator, Radarski senzori, Ultrazvučni senzori, Industrija nafte i gasa
    ... 3th ed, Chapter 7, Springer, 2003. 2. Dr. Dragan Stanković, "Fizičko tehnička merenja," Univerzitet u Beogradu, 1997. 3. Jon S. Wilson, "Sensor Technology", Chapter 10, Elsevier, 2005. 4. Prezentacija iz predmeta 'Metrologija i standardizacija, RGF, Univerzitet u Beogradu 5. Transactions In Measurement ...
    ... у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The 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 ...

  • Optimizacija i planiranje površinskih kopova stohastičkim modelima

    Dejan R. Stevanović (2015-05-29)
    Savremeno rudarstvo izloženo je stalnom trendu pogoršanja uslova poslovanja.Mogućnost ostvarenja ekonomskih i drugih ciljeva rudarskog projektakompromitovana je stalnim pogoršanjem kvaliteta ležišta na kojima se vršieksploatacija, kao i značajnoj dozi neizvesnosti povezane sa geološkim,ekonomskim i tehničkim parametrima proizvodnje. U ovako kompleksnimuslovima poslovanja, matematički modeli sposobni da odgovore značajnimizazovima, odnosno ponude optimalna rešenja kojima se garantuje maksimalnoispunjenje projektovanih ciljeva, nameću se kao neophodnost.Trenutni, konvencionalni pristup optimizaciji i planiranju površinskih kopovazasniva se na algoritmima, razvijenim sredinom prošlog veka čije je opšteobeležje deterministički ...
    površinski kop, planiranje, optimizacija, stohastički modeli, kontrola kvaliteta uglja, neizvesnost.
    ... design, Mining Technology, Vol. 111, str. 82-87. Dimitrakopoulos R, Ramazan S, 2008, Stochastic integer programming for optimizing long term production schedules of open pit mines: methods, application and value of stochastic solutions, Mining Technology, Transactions of the Institute of Mining and Metallurgy ...
    ... pit limits, production schedules, multiple orebody scenarios and sensitivity analysis, Mining Technology, vol. 118, str. 80-91 Allen H, Aspects of evaulating mining projects, Imperial College of Since and Technology, London, UK, pristupljeno 05.06. 2013. god, dostupno na: http://www.maden.org.tr/resi ...
    ... discounted economic block values, Mining Technology, vol. 118, str. 1-12. Aykul H, Yalcın E, Ediz I.G, Dixon-Hardy D.W, Akcakoca H, 2007, Equipment selection for high selectiveexcavation surface coal mining, The Journal of The Southern African Institute of Mining and Metallurgy, vol. 107, str. 195-210 ...

  • Optimizacija i planiranje površinskih kopova stohastičkim modelima

    Dejan R. Stevanović (2015-05-29)
    Savremeno rudarstvo izloženo je stalnom trendu pogoršanja uslova poslovanja.Mogućnost ostvarenja ekonomskih i drugih ciljeva rudarskog projektakompromitovana je stalnim pogoršanjem kvaliteta ležišta na kojima se vršieksploatacija, kao i značajnoj dozi neizvesnosti povezane sa geološkim,ekonomskim i tehničkim parametrima proizvodnje. U ovako kompleksnimuslovima poslovanja, matematički modeli sposobni da odgovore značajnimizazovima, odnosno ponude optimalna rešenja kojima se garantuje maksimalnoispunjenje projektovanih ciljeva, nameću se kao neophodnost.Trenutni, konvencionalni pristup optimizaciji i planiranju površinskih kopovazasniva se na algoritmima, razvijenim sredinom prošlog veka čije je opšteobeležje deterministički ...
    površinski kop, planiranje, optimizacija, stohastički modeli, kontrola kvaliteta uglja, neizvesnost.
    ... design, Mining Technology, Vol. 111, str. 82-87. Dimitrakopoulos R, Ramazan S, 2008, Stochastic integer programming for optimizing long term production schedules of open pit mines: methods, application and value of stochastic solutions, Mining Technology, Transactions of the Institute of Mining and Metallurgy ...
    ... pit limits, production schedules, multiple orebody scenarios and sensitivity analysis, Mining Technology, vol. 118, str. 80-91 Allen H, Aspects of evaulating mining projects, Imperial College of Since and Technology, London, UK, pristupljeno 05.06. 2013. god, dostupno na: http://www.maden.org.tr/resi ...
    ... discounted economic block values, Mining Technology, vol. 118, str. 1-12. Aykul H, Yalcın E, Ediz I.G, Dixon-Hardy D.W, Akcakoca H, 2007, Equipment selection for high selectiveexcavation surface coal mining, The Journal of The Southern African Institute of Mining and Metallurgy, vol. 107, str. 195-210 ...

  • Preparation of Multimedia Document “YU Rock Scene”

    Milena Obradović, Aleksandra Arsenijević, Mihailo Škorić (2017)
    SUMMARY: This study will present the preparation process of a multimedia document entitled YU ROCK SCENE in which participants were senior students of undergraduate studies of the Department of Library and Information Science at the University of Belgrade Faculty of Philology during the academic year 2014/2015, as a part of the subject Multimedia Documents. This study gives an overview of the historical development of rock and roll in the territory of the former Yugoslavia, rock scene in Yugoslav republics, ...
    multimedia document, library science, information science, rock and roll, music, Yugoslavia
    ... professions from radio, film, theatre and press. The programmes followed newspapers in creation of televi- sion content, as well as the development of technology. Drama series, documentaries Infotheca Vol. 16, No. 1–2, August 2016 119 Obradović M., et. al, “YU Rock Scene”, pp. 111–127 and entertainment ...
    ... у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The 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 ...

  • Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia

    Bojan Kostić, Pavle Tančić, Natalija Batoćanin (2024)
    geohemija granata, retke zemlje, fluidne inkluzije, skarnovsko ležište Rudnik