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Упит dcterms_subject_txt:grain size distribution

508 items

  • Application of VIКOR method in the selection of an optimal splution of excavation “Borska Reka” ore deposit

    Sanja Bajić, Dragoljub Bajić, Branko Glušćević, Radmila Gaćina (2023)

  • Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja

    Branko Kostić, Dejan Prelević, Sabina Kovač, Ksenija Eraković, Dragana Životić (2022)
    Ugljevi niskog ranga – ligniti u Republici Srbiji predstavljaju glavnu energetsku sirovinu koja se koristi za proizvodnju električne energije. Rudarstvo u Srbiji doprinosi bruto dodatoj vrednosti sa 1,8% (2020; https://publikacije.stat.gov.rs/). Sagorevanjem ugljeva niskog ranga u termoelektranama generišu se velike količine elektrofilterskog pepela i pepela, koje često predstavljaju jedan od izvora zagađenja životne sredine usled sadržaja toksičnih elemenata. Dalja upotreba produkata sagorevanja zavisi od njihovog sastava i sadržaja toksičnih mikroelemenata. Svakodnevno sagorevanje lignita u termoelektranama uslovljava konstantan monitoring potencijalno toksičnih ...
    ugalj, produkti sagorevanja, XRF, ICP-MS

  • 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
    ... precursors. On the contrary, carbon samples treated with LiOH and NaOH maintained their microspherical structures but with different particle size for the whole order of size. • All investigated samples showed high affinity for lead cadmium and zinc ions. Samples activated with KOH showed better removal of ...
    ... at a fixed temperature). Using BJH (Barrett, Joyner and Halenda) method [41], for every sample from desorption branch of the nitrogen isotherm pore-size distributions were calculated. In addition, mesopore surface (Smeso) and micropore volume (Vmicro) were also calculated from the isotherms. By using ...
    ... and Figure 4b for fructose. Also, for a better comparison, the influence of different activation agents on structure, porosity developments and pore-size distributions were determined and presented as inserts in Figure 4 (insets 1, 2 and 3). As it is clear from Figure 4a and b, for all samples similar ...

  • 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)
    ... The ruthenium complex is characterised by a couple of peaks from 565 to 573 with a peak at 569.3 having the highest intensity (Fig. 2A). This distribution is caused by the broad natural abundance of different ruthenium isotopes ranging from 96Ru to 104Ru. The original [RuCl2(bipy)2]Cl (mass 519.8) ...
    ... analysis of lysophospholipids. In contrast, the peak group for the corresponding platinum complex is found from 494 to 498 in relation to the broad distribution of natural platinum isotopes (Fig. 2B). The LPC peak at 496.3 was completely covered by the platinum metal complex. Thus, only the sodium adduct ...
    ... 2). The ruthenium complex is characterised by a couple of peaks from 565 to 573 with a peak at 569.3 having the highest intensity (Fig. 2A). This distribution is caused by the broad natural abundance of different ruthenium isotopes ranging from °°Ru to '!“Ru. The original [RuCl(bipy)sJCl (mass 519.8) is ...

  • Determination of Mechanical Properties of Altered Dacite by Laboratory Methods

    Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović (2021)
    This paper presents a methodology for determining the uniaxial and triaxial compressive strength of heterogeneous material composed of dacite (D) and altered dacite (AD). A zone of gradual transition from altered dacite to dacite was observed in the rock mass. The mechanical properties of the rock material in that zone were determined by laboratory tests of composite samples that consisted of rock material discs. However, the functional dependence on the strength parameter alteration of the rock material (UCS, intact ...
    Geology, Geotechnical Engineering, Engineering Geology
    ... tly influenced by microstructural characteristics, the most important of which are: the participation of the main mineral elements [12], mineral grain size [13], arrangement of mineral grains and their shape [14], mutual contact between individual mineral grains [15], and level of alteration [16]. In ...
    ... and AD samples showed that sanidine and quartz predominate in D. The strength parameters of the rock material are affected mainly by the content and size of quartz crystals. So, as the content of smaller quartz particles increases, the compressive strength increases. In the AD sample, the process of quartz ...
    ... separate discs [4] was shown as inadequate due to plaster failure at lower loads, causing the discs to displace and introducing non-uniform stress distribution throughout the disc interfaces. Tziallas et al. [1] found that the use of plaster to connect separate discs is unnecessary, considering the pattern ...

  • Efficiency and lifetime of medium voltage transformers

    Snežana Aleksandrović, Vesna Damnjanović (2017)

  • Hidrološki i hidraulički mehanizam isticanja vrela Rijeka Crnojevića

    Golub Ćulafić, Veljko Marinović, Branislav Petrović, Jelena Krstajić (2022)
    Rijeka Crnojevića predstavlja karstno (kraško) vrelo, koje u teritоrijalnom pogledu pripada Opštini Cetinje, u gеоlоškо-tеktоnskоm pоglеdu pripаdа zоni Visоkоg kršа (оblаst stаrе Crnе Gоrе), dоk prema hidrogeološkoj rejonizaciji spаdа u prоstоr Spoljašnjih Dinarida. Izvire iz Obodske (ili Crnojevića) pećine u selu Obod (81 m.n.m.). Voda koja ističe iz Obodske pećine vodi porijeklo od atmosferskih voda, koje se formiraju na prostoru Cetinjskog polja i Dobrskog sela. Vоdе nа оbоdu pоljа pоniru i kreću se uglаvnоm podzemnim kаvеrnаmа i kаnаlimа, nаstаlim ...
    Riјеkа Crnoјеvićа, karstnо vrelo, mehanizmi isticanja

  • Post Early Miocenevertical-axis clockwise rotation in the West Vardar Zone of Serbia

    Vesna Lesić, Emo Marton, Vesna Cvetkov, Dragana Jovanović (2018)
    ... both of Oligocene age. Samples were drilled and oriented in situ both by magnetic and sun compasses. In the laboratory samples were cut into standard size specimens, then subjected to standard paleomagnetic measurements which included the measurement of the natural remanent magnetization, followed by ...

  • Српски језик у дигиталном добу -- The Serbian Language in the Digital Age

    Duško Vitas, Ljubomir Popović, Cvetana Krstev, Ivan Obradović, Gordana Pavlović-Lažetić, Mladen Stanojević (2012)
    Serbian language
    ... of domains, number and size of existing speech corpora, amount and va- riety of available speech-based applications ‚ Machine Translation: uality of existing MT tech- nologies, number of language pairs covered, cover- age of linguistic phenomena and domains, quality and size of existing parallel corpora ...
    ... and do- mains, amount and variety of available applications, quality and size of existing (annotated) text corpora, quality and coverage of existing lexical resources (e. g., WordNet) and grammars ‚ Resources: uality and size of existing text corpora, speech corpora andparallel corpora, quality and ...
    ... generated from these words. 3.2.4 Syntax, text linguistics In terms of distribution of sentence constituents (sub- ject, predicate, object, etc.), Serbian belongs to SVO languages with free word order (more precisely, with free distribution of mobile sentence constituents). is means that, in general, all ...

  • Mesozoic carbonate rocks in Serbia used as dimension stone

    Vesna Matović, Tijana Vojnović Ćalić (2016)
    The building industry in Serbia uses, to a great extent, imported natural stone for architectural purposes. The significance of local deposits, particularly limestones, is not adequately perceived despite the country’s abundance of these valuable resources. Therefore, this study focuses on Serbia’s Mesozoic carbonate rocks, specifically on the deposits of four selected quarries: Klisura, Skrzut, Struganik, and Tisnica. The quality and prospects of the application of these limestones has not yet been the subject of a detailed, comprehensive investigation. Therefore, ...
    Ukrasni kamen, Mezozoik, Krečnjak, Srbija, Petrografija, Fizičko-mehanička svojstva
    ... crucial criterions for the profitable production of dimension stone are the soundness of the deposit (possibility of block production of a suitable size) and market demand (Luodes et al. 2000). Despite the fact that concrete and glass were the prin- cipal materials in architectural design during ...
    ... y, the rock mass is fragmented into blocks by a system of faults and fractures that reduce the possibility of extracting blocks of commercial size. The Struganik quarry has been exploited for architectural stone for over three decades. It is situated in western Serbia, within the territory ...
    ... light connected to a Leica DC 300 digital camera. The thin sections were used to determine the mineral composition and microtextural features (size and type of allochem) for the purpose of rock classification, according to Folk (1959) and Flugel (2004). The CaO and MgO contents were determined ...

  • Geoloski profil planine Avale (severna Šumadija) - uvid u litostratigrafiju i tektonske strukture

    Marinko Toljić, Bojan Glavaš-Trbić, Maja Maleš, Nikola Ranđelović (2022)
    Mezozojske formacije Šumadije dele tektonsko-stratigrafsku evoluciju južnijih delova suture jedinica Adrijskog i Evropskog afiniteta, uključujući gornjojursku obdukciju, krednu subdukciju i paleogenu kontinentalnu koliziju. Finalni rezultat dugovremene evolucije u geodinamički složenom ambijentu su komplikovani tektonski i litostratigrafski odnosi različitih mezozojskih formacija suture. Geološki profil kroz planinu Avalu omogućava uvid u skoro potpunu sukcesiju mezozojskih formacija i prostorne pozicije i kinematiku značajnih tektonskih struktura najsevernijih segmenata suture u Šumadiji. U tektonskom kontekstu, mezozojske formacije okoline Beograda najčešće su interpretirane kao deo Istočne ...
    sutura, parafliš, bazalna navlaka, transkurentni rased

  • Towards Better Valorisation of Industrial Minerals andRocks in Serbia—Case Study of Industrial Clays

    Vladimir Simić, Dragana Životić, Zoran Miladinović (2021)
    Management, Monitoring, Policy and Law,Nature and Landscape Conservation
    ... ogy and the achieved results. Table 3. Perspective deposits of bentonite and bentonite clays in Serbia [53]. Size of deposit after [44]. None of these deposits are in operation. Deposit Size of Deposit Quality (Grade) Method of Exploitation Number of Layers and Their Thickness (M) Depth ...
    ... deposits, bedded and lenticular, with uniform structure, thickness, and quality of mineral raw materials 100–150 150–200 300–400 Deposits of medium size, bedded and lenticular, with uniform structure, thick- ness, and quality of mineral raw mate- rial 50–100 100–200 200–300 2 Large deposits, ...
    ... and lenticular, without uniform structure and thick- ness, with variable quality of mineral raw materials - 50–100 100–200 Deposits of medium size, bedded and lenticular, without uniform structure - 25–50 50–150 Resources 2021, 10, 63 7 of 18 and thickness, with variable quality of ...

  • Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine

    Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić (2021)
    The production of lignite in large open-pit mines is mainly performed with continuously operating equipment, where bucket-wheel excavators, bucket-chain excavators, belt conveyors, and spreaders are the basic machines. Smaller machines, usually of discontinuous operating nature, are commonly categorized as auxiliary machines. This paper presents the research related to the analysis of auxiliary machine parameters with the case study for a hydraulic excavator. The purpose of the analysis was to develop a model of rating quality of service of the ...
    Fuzzy theory, hydraulic excavator, selection, quality of service, asset management

  • Application of machine learning for diagnosing the operation of a deep well pump in oil production

    Maja Trikić (2024)
    This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.
    deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost
    ... tree, Random forest and XGBoost AutoML Decision tree, Random forest and XGBoost Decision tree Number of instances per class 30 30 90 180 Test set size 50,098 50,098 50,098 50,098 Number of tests 9 3 9 3 Maximum accuracy (%) 86.005 84.516 97.900 98.174 Table 3. Organization of Tests into 4 Groups ...
    ... card can indicate the performance of the pump system. However, since sensors are located at the surface, degenerative effects caused by load distribution along the rod string can alter the card's shape, complicating analysis, especially in deep wells. Due to these challenges and the difficulty ...
    ... is important to use metrics that combine precision and recall. 6.3.2. Imbalanced datasets Imbalanced datasets refer to situations where the distribution of examples among different classes is not even or is biased. Most machine learning algorithms assume that classes are approximately equal in ...

  • 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
    ... methodology and format known as DELAS/DELAF, which is presented for French in [1]4. Serbian e-dictionaries of simple forms have reached a consid- erable size: they have a total of 122,000 entries [2]. Although we are continually enlarging our e-dictionaries of simple words, we have taken a further step to- ...
    ... whereas for French it is 1.29. The calculation is performed on the basis of 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 ...

  • Definition of groundwater genesis and circulation conditions of the complex hydrogeological karst system Mlava–Belosavac–Belosavac-2 (eastern Serbia)

    Ljiljana Vasić, Saša Milanović, Zoran Stevanović, Laszlo Palcsu (2020)
    Geochemistry and Petrology

  • Izdvajanje vode iz prirodnog gasa

    Dejan Nedeljkov (2024)
    U radu je istaknuto važnost prirodnog gasa kao vitalna komponenta svetske energetike.Spada u najsigurnije,najčistije i najkorisnije fosilno gorivo. Sama pojava vode u vidu vlage u gasu je pokazatelj lošeg kvaliteta gasa. parametri koji mogu dovesti do lošeg kvaliteta prirodnog gasa kao pokazatelj je Wobbe index.U okviru istraživanja u master radu glavni problem funkcionisanja na KPG Paliću predstavlja vlaga u gasu,takođe se može zaključiti da kvalitet gasa zavisi od Wobbe indeksa odnosno, što je Wobbe veći, čistiji je gas, ili ...
    prirodni gas, separatori, separacija, grejači, čileri, tačka rose, Wobbe indeks
    ... TM O n BR O O — 5 A.P. Szilas: Production and Transportation od Oil and Gas, Elsevier, Budapest, 1986,str.108 % Artur Gerunda: How to Size Liquid — vapor separators, Chemical Enginering,str.89 9 5. SAKUPLJANJE, SEPARACIJA, PRIPREMA I TRANSPORT GASA Sabirno - transportni sistem čine ...
    ... separatori zbog toga se daje upoređenje njihovih karakteristika. !' Ken Ranold, Maurice Steward: Designing oil and gas production system – How to size and select three phase separators, World Oil, Decembar, 1984., str. 68 18 Horizontalni separatori su produktivniji i efikasniji od vertikalnih ...
    ... IIL, 2012. godine [11] A.P. Szilas: Production and Transportation od Oil and Gas, Elsevier, Budapest, 1986. godine [12] Artur Gerunda: How to Size Liquid – vapor separators, Chemical Enginering. [13] Andre Giraud, Xavier BOY: Geopolitique du petrol et du gaz, Edition Technip, Paris, 1987. godine ...

  • Review: Methodological approaches and research techniques for addressing construction and remediation problems in karst reservoirs

    Saša Milanović, Ljiljana Vasić (2021)
    Earth and Planetary Sciences (miscellaneous), Water Science and Technology

  • Structural characterization of traditional pottery produced from local clay, Rujište (Ražanj, Central Serbia), in an effort to preserve its geoheritage

    Maja Milošević, Biljana Đorđević, Alena Zdravković (2021)
    ... spectrometer (EDS), a wavelength-dispersive spectrometer (WDS) and a cathodoluminescence detector (CL) were applied to determine the morphology and grain size assessment of minerals as well as their chemical composition. Raw clay, from which investigated sample of pottery was produced, largely falls ...

  • Influence of Ag doping on the morphological and magnetic properties in CuO nanopowders

    Maria Čebela, Uroš Čakar, Vesna Lojpur, Maja Milošević, Sanja Krstić, Vladimir Dodevski, Milena Rosić (2023)
    ... Ag in order to improve further its multiferroic properties. Compared with CuO, we observed small changes in magnetic properties in Cu, „Ag,O. The size and morphology of the particles were successfully determined by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). ...