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Упит dcterms_subject_txt:chemical analysis

845 items

  • Coal homogenization stockyard sizing “Tamnava – Zapad” case study

    Božo Kolonja, Dinko Knežević, Ranka Stanković, Dejan Stevanović, Detlef Trummer (2016)

  • Izbor rotornih bagera za proces revitalizacije: primer rotornih bagera SRs 1200 u rudarskom basenu Kolubara

    Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Filip Miletić, Goran Todorović, Dragan Novaković (2020)
    Revitalizacija je proces ili skup tehničkih zahvata na mašini kojim se vrši zamena svih dotrajalih ili oštećenih delova metalne konstrukcije. Sastavni deo procesa revitalizacije je i modernizacija zastarele elektro-mašinske opreme. Principi revitalizacije sasvim sigurno nisu sadržani u okviru redovnog godišnjeg ili dnevnog održavanja. Oni predstavljaju održavanje onih veličina koje su značajne za mašinu kao celinu (u ovom slučaju rotorni bager). U ovom radu su analizirani rotorni bageri oznake SRs 1200. Na površinskim kopovima rudarskog basena Kolubara takvih bagera ima ...
    Rotorni bageri, revitalizacija, SRs1200
    ... Kolubara 6 Novaković Dragan, EPS Beograd – ogranak RB Kolubara 10 the already revitalized SRs 1201 (G2) excavator was excluded from the analysis. For the selection of the SRs1200 bucket-wheel excavator for the revitalization process, two methods of multi-criteria decision making, VIKOR ...
    ... Assessment Model for Ranking of Renewable and Non-Renewable Transportation Fuel Vehicles. Energy 2009, 34, 112–125 [7] Tsaur R. C.: Decision risk analysis for an interval TOPSIS method. Appl. Math. Comput. 2011, 218, 4295–4304 [8] Tavana M., Di Caprio D., Santos-Alteaga F.: An extended stochastic ...

  • Crystal structure of K3EuSi2O7

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović (2021)
    alkalni silikati elemenata retkih zemalja, kristalna struktura, sinteza metodom fluksa, rendgenska difrakcija na monokristalu

  • Аnaliza mogućnosti povećanja nagiba završne kosine površinskog kopa “Podbraćan”

    Vladimir Čebašek, Veljko Rupar (2018)
    Eksploatacijom boksita iz ležišta "Podbraćan" formiran je površinski kop sa maksimalnom visinom zavšne kosine od 280 m. Redovnom kontrolom stabilnosti trenutnog stanja kosina površinskog kopa utvrđeno je da faktor sigurnosti iznosi Fs = 1.71 – 1.85, a što je ukazalo da postoji mogućnost povećanja nagiba kosine. U radu je prikazan postupak analize mogućnosti povećanja nagiba završne kosine površinskog kopa "Podbraćan".
    stabilnost kosina, povećanje nagiba kosina, metoda konačnih elemenata
    ... ANALIZA MOGUĆNOSTI POVEĆANJA NAGIBA ZAVRŠNE KOSINE POVRŠINSKOG KOPA “PODBRAĆAN” ANALYSIS OF THE POSSIBILITIES OF OPEN PIT "PODBRAĆAN" FINAL SLOPE ANGLE INCREASING DOI:------------------------- Vladimir Čebašek1, Veljko Rupar2 1 Rudarsko-geološki fakultet, Đušina 7, 11000 Beograd ...
    ... mogućnosti povećanja nagiba završne kosine - Aneks, Rudarsko-geološki fakultet, Beograd, pp. , (2007) 3. D.V. Griffiths, P.A. Lane, Slope stability analysis by finite elements, Geotechnique 49, No. 3, pp. 387-403, (1999) 4. E. Hoek, J.W. Bray, Rock slope stability, Revised Third Edition, Institution of ...

  • Infotheca (Q25460443) in Wikidata

    Ranka Stanković, Lazar Davidović (2021)
    Vikipodaci su baza znanja Zadužbine Vikimedija koja predstavlja zajednički izvor različitih vrsta podataka koje koriste ne samo drugi Vikipedijini projekti, već sve više i brojne aplikacije semantičkog veba. U ovom radu ćemo prezentovati primer integracije Vikipodataka sa digitalnim bibliotekama i eksternim sistemima, kao i mogućnost ubrzanja pripreme i unosa podataka na primeru radova iz časopisa za digitalnu humanistiku Infoteka.
    semantički veb,otvoreni povezani podaci, vikpodaci,Infoteka, metapodaci časopisa

  • Energetska bezbednost sektora prirodnog gasa Srbije

    Aleksandar Madžarević, Predrag Jovančić, Miroslav Crnogorac (2023)
    U prve dve decenije 21. veka obezbeđivanje sigurnosti snabdevanja prirodnim gasom domaćeg tržišta bio je jedan od prioriteta razvoja energetike Srbije. Istovremeno, aspekt sigurnog snabdevanja bio je neizostavni deo slagalice stvaranja energetske bezbednosti. Izražena uvozna zavisnost je dominantna karakteristika sektora prirodnog gasa, tačnije, Republika Srbija je snažno zavisna od ruskog gasa, sa više od 80% uvezenih količina gasa, a do pre dve godine snabdevala se isključivo kroz jednu interkonekciju. U radu se razmatra aktuelna situacija u sektoru prirodnog ...
    N-1, IDUPS, energetska bezbednost, sigurnost snabdevanja
    ... security of natural gas supply to Serbia, as well as its vulnerability to interruptions in international supply chains. Through the paper, an analysis of the energy security of the natural gas sector assessed by the N-1 index, IDUPS and the parameter of infrastructure development of the sector ...

  • An arid phase in the Internal Dinarides during the early to middle Miocene: Inferences from Mg-clays in the Pranjani Basin (Serbia)

    N. Andrić-Tomašević, V. Simić, O. Mandic, D. Životić, M. Suárez, E. García-Romero (2020)
    Paleontology,Earth-Surface Processes,Ecology, Evolution, Behavior and Systematics,Oceanography
    ... intensity of each mineral by the sum of the main-peaks intensities of all minerals (see Moore and Reynolds, 1997 for details). Samples for chemical analysis were crushed, milled and pulverised to 85% < 75 μm. Major elements were analysed using fused beads with lithium borate, acid digestion and the ...
    ... using two-acid digestion (based on a combination of 2:1 HNO3: HCl) and either ICP-AES or ICP-MS techniques (at ALS Laboratory). The results of chemical analysis are presented in Tables 2 and 3. Detection limits for each element are given in the last column of Table 3. Particle morphology and textural ...
    ... sepiolite are typically grouped in bundles (sensu García-Romero and Suárez, 2014). The laths are between 50 and 100 nm wide and grouped, Table 2 Chemical composition of studied samples (in wt%). Clay minerals, Other minerals Sme Anl Sme, Sep Sep, Sme Sep Sep Dol Sep Dol Sample AND-1 ...

  • Еволуција напонског поља подручја Интерних Динарида у Србији током алпске орогенезе

    Ana S. Mladenović (2015-06-19)
    Циљ ове докторске дисертације био је реконструкција еволуције напонског пољаЗемљине коре у подручју Интерних Динарида у Србији током Алпске орогенезе.Истраживања за потребе решавања овог проблема су изведена у два дела. Првидео обухватао је анализу палеонапона на дефинисаном подручју истраживања,док се други део односио на анализу тренутно активног поља напона у овом делуБалканског полуострва. Истраживано подручје обухвата унутрашњи деоДинарског орогеног појаса, који се простире у централној и западној Србији. Собзиром на циљ истраживања, истраживано подручје је дефинисано тако даобухвата три ...
    Интерни Динариди, анализа палеонапона, фокални механизмиземљотреса, напонско поље, тектоно-магматски догађаји

  • Coal: exploration, reserves, and utilization

    Dragana Životić, Gligor Jovanovski, Vladimir Simić, Ivan Boev, Vesna Cvetkov, Petre Makreski, Dušan Polomčić, Vesna Ristić Vakanjac (2024)
    Coal exploration is a very demanding task, highly dependent on geological and economic factors and the utilization of coal. This lecture text includes information on a variety of geological techniques used in the exploration of coal and coal-bearing sequences, as well as on the calculation, assessment, classification, and reporting of coal resources and reserves. The main features of coal utilization and some environmental aspects are explained briefly. Special attention is paid to the by-products of coal utilization, their uses, ...
    угаљ, истраживање, ресурси, резерве, коришћење, сагоревање, карбонизација, гасификација, угљенични материјали
    ... and anomalies in the measured fields. Analysis and interpretation of anomalies provides information about the geological structure and composition of the Earth's crust. ChemTexts (2024) 10:1 As mentioned above, geophysical methods are based on analysis of the distribution of values of certain ...
    ... sampling. Laboratory tech- niques include a number of different analyses [6], such as proximate and ultimate analyses; the determination of the chemical composition and thermomechanical proper- ties of ash and the thermal, mechanical, and petrographic @ Springer ChemTexts (2024) 10:1 properties ...
    ... the production of metallurgical coke by carbonization [8], liquid fuels by direct or indirect liquefaction [9], syngas by gasification [10], and chemical products [11], as well as the preparation of functional carbon materials [12-15]. Coal by-products from different processes can be transformed ...

  • 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. ...

  • The Use of the Omeka Semantic Platform for the Development of the University of Belgrade, Faculty of Mining and Geology Digital Repository

    Petar Popović, Mihailo Škorić, Biljana Rujević (2021)
    Under the regulations of the Ministry of Education, Science and technological Development, a digital repository based on the Omeka S data storage platform has been developed for the Faculty of Mining and Geology. The platform has been upgraded with the required modular extensions, Solr index and automatic OCR. Furthermore, document indexing and search have been fine-tuned with the aid of e-dictionaries of the Serbian language, which has brought about outstanding results in terms of usage facilitation and overall ...
    Дигитални репозиторијум, Омека, претрега дигиталних библиотека

  • Determination of parameters for wet grinding of phosphates in a laboratory ball mill and classification in a hydrocyclone

    Predrag Lazić, Đurica Nikšić, Vladan Živković, Nemanja Todorović (2024)
    Компанија Elixir Прахово у свом производном процесу користи суво млевење сировог фосфата за своју производњу. Међутим, због повећане влаге у сировом фосфату која изазива потешкоће у фази сувог млевења, разматра се могућност увођења мокрог млевења у индустријском постројењу у Прахову. Влага улазног сировог фосфата варира од барже до барже, и креће се у границама 5-10% H2O, што је јако високо за процес сувог млевења а ствара одређене проблеме и на транспортном систему (систем редлерских транспортери). За сагледавање могућности мокрог млевења ...
    мокро млевење, фосфат, класирање, хидроциклон

  • Процена ризика од загађивања водних ресурса под утицајем напуштених рударских радова на простору Србије

    Nebojša B. Atanacković (2018-08-31)
    Велики број напуштених рударских радова и ограничена средства за рекултивацијуи ремедијацију деградираних простора подстакле су развој метода за издвајањеприоритетних локација на које је потребно усмерити даља истраживања. У датомконтексту, у склопу израде дисертације спроведене су научно-истраживачкеактивности које су за предмет имале анализу утицаја значајнијих напуштенихрударских радова на водне ресурсе на простору Србије јужно од Саве и Дунава.Разматрање предметне проблематике извршено је кроз развој и примену семи-квантитативне методологије за анализу ризика од загађивања површинских иподземних вода на регионалној размери. Примењена ...
    анализа ризика, водни ресурси, водна тела, рудничке воде, рударскиотпад, аналитички хијерархијски процеси, кластер анализа, математичка теоријаатрибута, функције припадности, семи-квантитативне методе

  • Some models for determination of parameters of the soil oscillation law during blasting operations

    Suzana Lutovac, Dragan Medenica, Branko Gluščević, Rade Tokalić, Čedomir Beljić (2018)

  • Machine Learning and Deep Neural Network-Based Lemmatization and Morphosyntactic Tagging for Serbian

    Ranka Stanković, Branislava Šandrih, Cvetana Krstev, Miloš Utvić, Mihailo Škorić (2020)
    The training of new tagger models for Serbian is primarily motivated by the enhancement of the existing tagset with the grammatical category of a gender. The harmonization of resources that were manually annotated within different projects over a long period of time was an important task, enabled by the development of tools that support partial automation. The supporting tools take into account different taggers and tagsets. This paper focuses on TreeTagger and spaCy taggers, and the annotation schema alignment ...
    Part-of-Speech tagging, lemmatization, corpus, evaluation, Serbian, morphological dictionary

  • An Approach to Efficient Processing of Multi-Word Units

    Cvetana Krstev, Ivan Obradović, Ranka Stanković, Duško Vitas (2013)
    Efficient processing of Multi-Word Units in the course of development of morphological MWU dictionaries is not easy to achieve, especially when languages with complex morphological structures are concerned, such as Serbian. Manual development of this type of dictionaries is a tedious and extremely slow process. To alleviate this problem we turned to our multipurpose software tool, dubbed LeXimir, in the production of lemmas for e-dictionaries of multi-word units. In addition to that, we developed a procedure aimed at making ...
    Natural Language Processing, Grammatical Category, Lexical Representation, MWU, multi-word unit

  • Dehydroicetexanes in sediments and crude oils: Possible markers for Cupressoideae

    Hans Peter Nytoft, Geir Kildahl-Andersen, Sofie Lindström, Frode Rise, Achim Bechtel, Danica Mitrović, Nataša Đoković, Dragana Životić, Ksenija A. Stojanović (2019)
    Two previously unidentified dehydroabietane isomers were isolated from Miocene Serbian lignite and Rhaetian (Late Triassic) coaly mudstones from South Sweden and characterized using NMRspectroscopy as cis- and trans-dehydroicetexane. Both have a 9(10?20)-abeo-abietane or icetexane skeleton, consisting of a 6-7-6 tricyclic framework with seven carbons in ring B instead of the usual six in common diterpanes of the abietane-type. Dehydroicetexanes can be detected using GC-MS-MS in m/z 270?146 chromatograms without interference from dehydroabietane or other isomers. Dehydroicetexanes are often abundant ...
    Geochemistry and Petrology
    ... Characterization of lignite lithotypes from the ‘‘Kovin” deposit (Serbia) – implications from petrographic, biomarker and isotopic analysis. Journal of the Serbian Chemical Society 82, 739–754. Mothana, R.A., Al-Said, M.S., Al-Musayeib, N.M., El Gamal, A.A., Al-Massarani, S.M., Al-Rehaily, A.J., Abdulkader ...
    ... 1D 1H NMR, 13C Z-restored spin-echo (Xia et al., 2008), DEPT135, 2D NOESY, 1H-1H COSY, 1H-13C HSQC, 1H-13C HSQC-TOCSY and 1H-13C HMBC. 1H and 13C chemical shifts in ppm were calibrated against residual CHCl3 (1H, 7.26 ppm) or CDCl3 (13C, 77.00 ppm). For one of the compounds, we were unable to obtain ...
    ... Nei- ther increasing the temperature to 308 K or using regular decou- pled single-pulse 13C experiments improved the spectral quality. The two 13C chemical shifts of this compound in Table 1 reported to only one decimal place are therefore obtained from HSQC and HMBC spectra, and not observed in the 1D ...

  • Mio-Pliocene Geodynamics and its Stratigraphic Consequences in the Area of Avala Mt. (Belgrade, Serbia)

    Ljupko Rundić, Meri Ganić, Slobodan Knežević, Dejan Radivojević (2017)

  • Tectono-lithostratigraphic model of the Northern Banat Miocene sediments (Pannonian Basin, Serbia)

    Dejan Radivojević, Ljupko Rundić (2017)

  • Molecular and Isotope Composition of Biomarkers in Immature Oil Shale and its Liquid Pyrolysis Products (Open and Closed System)

    Gordana Gajica, Aleksandra Šajnovic, Jan Schwarzbauer, Aleksandar Kostić, Branimir Jovančićević, Ksenija Stojanović (2021)
    The molecular and isotopic composition of biomarkers in initial bitumen isolated from raw immature oil shale samples from the Lower Miocene Aleksinac Basin (Serbia) and liquid products (LPs) obtained by pyrolysis in open (OS) and closed systems (CS) are studied. The influence of pyrolysis type and variations of kerogen type on biomarkers composition and their isotopic signatures in LPs is determined. The molecular composition of the LPs from the OS pyrolysis is very similar to those in initial bitumen, independently ...