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Упит dcterms_subject_txt:chemical analysis

753 items

  • Differently shaped nanocrystalline (Fe, Y)3O4 and its adsorption efficiency toward inorganic arsenic species

    Biljana P Dojčinović, Boštjan Jančar, Lotfi Bessais, Aleksandar Kremenović, Nataša P Jović-Jovičić, Predrag T Banković, Dalibor M Stanković, Miloš Ognjanović, Bratislav V Antić (2019)
    Herein we report effects of partial substitution of Fe3+ by Y3+ in magnetite (Fe3O4) on morphology and inorganic arsenic species adsorption efficiency of the Fe3−xYxO4 nanoparticles formed. The series of Fe3−xYxO4 (x=0.00, 0.042 and 0.084, labeled as Y00, Y05 and Y10, respectively) was synthesized using co-precipitation followed by microwave-hydrothermal treatment (MW) at 200°C. With increase of yttrium content(xvalue), both the morphological inhomogeneity of the samples and the fraction of spinel nanorods as compared to spinel pseudospherical particles increased. By ...
    microstructure, microwave-hydrothermal synthesis, adsorption, magnetic nanoparticles, arsenic

  • The influence of alkyl polyglucosides (and highly ethoxylated alcohol boosters) on the phase behavior of a water/toluene/technical alkyl polyethoxylate microemulsion system

    Marija Ilic, Franz-Hubert Haegel, Vesna Pavelkic, Dragan Zlatanovic, Snezana Nikolic-Mandic, Aleksandar Lolic, Zoran Nedic (2016)
    The influence of additives (alkyl polyglucoside, Glucopon 600 CS UP and alcohol ethoxylate C18E100) on the behavior of the water/toluene/Lutensol ON 50 (technical oxoalcohol, i-C10E5) microemulsion system as a function of temperature and composition has been investigated. The phase behavior of the microemulsions was determined by vertical sections through the Gibbs phase prism (fish-like phase diagrams). Alkyl polyglucoside shifts the one phase region to lower temperatures compared with water/toluene/Lutensol ON 50 mixtures. This is contrary to the expectation, considering ...
    микроемулзија, толуен, алкил полиглукозид, оксоалкохол етоксилат, појачивач ефикасности, „fish“ дијаграми
    ... system | Marija Ilic, Franz-Hubert Haegel, Vesna Pavelkic, Dragan Zlatanovic, Snezana Nikolic-Mandic, Aleksandar Lolic, Zoran Nedic | Chemical Industry and Chemical Engineering Quarterly | 2016 | | 10.2298/CICEQ141105015I http://dr.rgf.bg.ac.rs/s/repo/item/0008425 Дигитални репозиторијум Рударск ...
    ... publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Chemical Industry & Chemical Engineering Quarterly MARIJA ILIĆ! FRANZ-HUBERT HAEGEL? VESNA PAVELKIĆ? DRAGAN ZLATANOVIĆ“ SNEŽANA NIKOLIĆ-MANDIĆ* ALEKSANDAR LOLIĆ ...
    ... bg.ac.rs Paper received: 5 November, 2014 Paper revised: 13 May, 2015 Paper accepted: 20 May, 2015 ivailable on line at issociation of the Chemical Engineers of Serbia ACPE www.ache.org.rs/CICEQ Chem. Ind. Chem. Eng. Q. 22 (1) 27–32 (2016) CI&CEQ THE INFLUENCE OF ALKYL POLYGLUCO- SIDES ...

  • Design of the Opencast Coal Mine Drmno Dewatering System

    Vladimir Pavlović, Dušan Polomčić, Tomislav Šubaranović (2014)
    Development of mining in the opencast mine Drmno from Kostolac basin in Serbia is carried out in the increasingly complex geological and hydro geological conditions with the decline of the coal seams to the alluvial part of Europe's largest river Danube. Greater depth and inflow of groundwater significantly increase costs for dewatering facilities construction with the requirement for optimizing of this more and more important surface mining process. Making decision on screen construction in the opencast mine with redesign ...
    dewatering system, groundwater, hydrodynamic model, dewatering wells, screen, reliability, environmental effects.

  • Human factor risk management procedures applied in the case of open pit mine

    Snežana Kirin, Aleksandar Sedmak, Wei Li, Miodrag Brzaković, Igor Miljanović, Ana Petrović, Simon Sedmak (2021)
    Risk management aims to provide a controlled work environment to ensure the safe operation of the high-risk systems. It is a dynamic process which work in a continual state of change. The issue of human factor risk and rules and regulations in open pit mine is a main focus of this paper in order to develop predictive models of behavior of workers in relation to compliance with the procedures and rules. Presented survey was conducted in open pit coal ...
    Upravljanje rizikom, ljudski faktor, bager sa kašikom, metod konačnih elemenata

  • Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry

    Steven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti (2021)
    Self-engineering is a relatively new branch of knowledge that aims to understand how systems could “autonomously” re-configure or repair themselves without the intervention of the operators. A direct field of application is within the maintenance spectrum. Having systems or machines capable of self-detecting or even self-repairing could represent a game-changer, in capital asset fields such as the mining industry in particular. This paper aims to investigate the possible benefits and challenges of self-engineering / self-maintenance concerning mining machines, specifically bucket-wheel ...
    self-engineering, self-maintenance, maintenance operations, mining industry, bucket-wheel excavator, gearbox revitalization

  • Analiza pouzdanosti dozera angažovanih na površinskim kopovima RB Kolubara

    Filip Miletić, Dragan Milčić, Miloš Tanasijević, Miloš Milovančević (2021)
    U radu je izvršena uporedna analiza pouzdanosti transportnih sistema dozera koji rade na površinskim kopovima Rudarskog basena Kolubara. Period za koji je vršena analiza je prvih deset godina eksploatacije. Efikasnost tehnološkog procesa na otkopavanju korisne mineralne sirovine i otkrivke u velikoj meri zavisi od rada dozera. Iskorišćene su matematičke metode za aproksimaciju i identifikaciju zabeleženih vremena u radu, kako bi se dobili analitički pokazatelji pouzdanosti. Na ovaj način se bitno podiže kvalitet upravljanja procesom eksploatacije i održavanja mašina na ...
    dozeri, pouzdanost, kolubarski ugljeni basen
    ... pouzdanost, kolubarski ugljeni basen Abstract: The paper presents a comparative reliability analysis of the dozers transport systems which working on the open pit mines of the Kolubara Mining Basin. Analysis period is first ten years of exploitation. Efficiency of process on excavation of mineral raw ...
    ... arski, sa parametrom oblika i parametrom razmere η. [7] Parametri raspodele mogu se odrediti analitički, metodom najmanjih kvadrata (Regression analysis) [8] i grafički. Analitički postupak daje nešto tačnije rezultate. Primenom grafičkih metoda može se oceniti tačnost razvijenog modela zakona raspodele ...
    ... mašinskih delova i sistema u okruženju Microsoft Excel, Infoteh–Jahorina Vol. 10, Ref. C-8, p. 273-277, Mart 2011; [8] Ashish S., Muni S. Regression analysis - Theory, Methods, and Applications, Springer-Verlag New York, 1990.; [9] Milčić D. Pouzdanost mašinskih sistema, Univerzitet u Nišu, Mašinski fakultet ...

  • Surface functional groups and degree of carbonization of selected chars from different processes and feedstock

    Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann (2022)
    The knowledge ofthe structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness ...
    Biougalj, različiti procesi dobijanja, različite sirovine, površinski aktivne grupe, x-ray, FT-IR,XPS
    ... for the investigations in Belgrade (SEM, XRD, FT-IR, Raman, titrations), the chemical analyses, XPS, and SIP in Julich. Subsamples were taken from these samples for each ofthe determinations. For each of the chemical analysis (C, H, N; oxygen; other elements), except ash determination, three subsamples ...
    ... use as a fuel. X-ray photoelectron spectroscopy XPS yields results on the chemical composition in a thin layer at the surface of material, these results may be considerably different from those of the chemical analysis of bulk materials. Despite that fact, the overview of the elements (Table 6) ...
    ... amounts of K2p. https://doi.org/10.1371/journal.pone.0277365.t006 corresponds to the abundance found by chemical analysis and by XRD. The deviation of the O/C ratio from XPS and element analysis (Fig 2) was largest for the activated carbons and PW?700g. The lower O/C ratio for AC2 obtained by XPS ...

  • The correlation of Upper Miocene lithostratigraphic units of the southern part of the Pannonian basin

    Filip Anđelković, Dejan Radivojević (2019)
    gornji miocen, litostratigrafske jedinice, formacije, Panonski basen
    ... basin is a classical back-arc basin formed during Miocene times. The rifting took place along asymmetric simple shear extensional mechanism. The analysis of syn- kinematic reflectors demonstrates that normal faulting migrates in time and space and took place on a wide Miocene time interval (roughly ...
    ... this paper is the southern part of the Pannonian Basin, and more specifically, the parts which have been well-documented and where the formational analysis has been carried out. The concrete areas are: North Banat (Serbia), southeastern parts of Hungary (Great Hungarian Plain), as well as some parts ...
    ... Magyar, I., Horváth, F., Cloething, S., (2016). The link between tectonics and sedimentation in back-arc basins: New genetic constraints from the analysis of the Pannonian Basin. Tectonics. 35, pp.1526-1559 2. Balázs, A., Burov, E., Mațenco, L., Vogt, K., Francois, T., Cloething, S., (2017). Symmetry ...

  • Hydrochemical features and their controlling factors in the Kucaj-Beljanica Massif, Serbia

    Fen Huang, Ljiljana Vasic, Xia Wu, Jianhua Cao, Saša Milanovic (2019)
    Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Analiza sistema odvodnjavanja površinskog kopa Drmno od podzemnih voda sa severnim savršenim ekranom

    Tomislav Šubaranović, Dušan Polomčić, Vladimir Pavlović (2019)
    Izrada nesavršenog ekrana do drugog sloja uglja na površinskom kopu Drmno, pored zadržavanja postojećih standardnih metoda odvodnjavanja od podzemnih voda linijama bunara, predviđena je poslednje decenije u celokupnoj rudarskoj projektnoj dokumentaciji. Iz objektivnih i subjektivnih razloga njegova realizacija nije ostvarena do danas. U međuvremenu je, uz dodatna geološka istraživanja i promenu dinamike i parametara sistema površinske eksploatacije, došlo do određenih značajnih prostornih promena geoloških i rudarskih uslova u eksploatacionom polju. Ovo je omogućilo preliminarno inoviranje pristupa procesu i konceptu ...
    podzemne vode, odvodnjavanje, bunari, ekran, dinamika, troškovi

  • Complex geophysical survey on solving the problem of water loss in the karst terrain reservoir

    Branislav Sretković, Dejan Vučković (2023)
    Geophysical surveys in karst terrain are always a specific challenge. Each of them requires a careful consideration of the problem, specific conditions on the ground, the selection of adequate methods applicable in that specific and unique karst area. But they should have one thing in common: a complex approach and looking at the problem from wider to narrower, with a gradual narrowing of the investigation area, increasing the spatial precision and resolution of the obtained data. On the example of ...

  • Analiza nosivosti vertikalno opterećenog šipa za potrebe izgradnje petlje „Merošina 1“ na autoputu E-80 deonica: Niš – Merošina

    Dragoslav Rakić, Nikola Božović, Miloš Stevanović, Milan Bogdanović (2023)
    U Srbiji je počela izgradnja autoputa E-80 koji će predstavljati saobraćajno čvorište zapadnog Balkana i biće deo glavne regionalne transportne mreže jugoistočne Evrope. Njegova ukupna dužina kroz Srbiju iznosi 77 km, a prva deonica u dužini od 5.5 km je završena i puštena u saobraćaj krajem jula 2023. god. To je prva od četiri deonice Sektora 1 čija je dužina 32.65 km. U sklopu petlje „Merošina 1“ izgrađen je nadvožnjak koji je oslonjen na devet stubnih mesta na međusobnom ...
    petlja Merošina 1, šip, probno opterećenje šipa, projektni pristup, granična stanja

  • Analiza primene višekriterijumskih metoda u optimizaciji izbora hidruličnih bagera na površinskim kopovima uglja

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Filip Miletić, Ivan Janković (2019)
    Hidraulični bageri primenjuju se u različitim oblastima privrede a najzastupljeniji su u građevinarstvu i rudarstvu. Na površinskim kopovima sa kontinualnim sistemima, klasifikuju kao pomoćna mehanizacija a na površinskim kopovima sa diskontinualnim sistemima, kao osnovna mehanizacija. Kako je u oba slučaja njihova primena neizostavna, važno je izvršiti adekvatnu analizu postojećih podataka, u cilju optimizacije izbora tipa hidrauličnog bagera u odnosu na uslove rada datog površinskog kopa. U radu su opisane različite višekriterijumske metode koje su korišćene za analizu hidrauličnih bagera. ...
    višekriterijumske metode, površinski kop uglja, pomoćna mehanizacija, hidraulični bager
    ... adequate analysis of the existing data in order to optimize the choice of the type of hydraulic excavator in relation to the working conditions of a particular open- cast mine. This paper aims to demonstrate the potential of multi-criteria optimization methods that are used in the analysis of hydraulic ...
    ... 5,5 8,4 8,2 Udobnost upravljanja 7,1 9,6 8,5 4. VIŠEKRITERIJUMSKE METODE Višekriterijumska analiza odlučivanja (Multi Criteria Decision Analysis - MCDA) je jedna od naj- značajnijih oblasti operacionih istraživanja koja je veo- ma brzo napredovala u poslednjih 20 godina [7]. Vi- šekriterijumsko ...
    ... Evoluti- onary Algorithms. Procedia Computer Science, 55, pp. 308–317, DOI:10.1016/j.procs.2015.07.054, 2015. [17] Tsaur R. C, Decision risk analysis for an interval TO- PSIS method. Applied Mathematics and Compu- tation 218(8), pp. 4295-4304, doi:10.1016/j.amc.- 2011.10.001, 2011. [18] Hudej ...

  • Towards Automatic Definition Extraction for Serbian

    Ranka Stanković, Cvetana Krstev, Rada Stijović, Mirjana Gočanin, Mihailo Škorić (2021)
    U radu su prikazani preliminarni rezultati automatske ekstrakcije kandidata za definicije rečnika iz nestrukturiranih tekstova na srpskom jeziku u cilju ubrzanja razvoja rečnika. Definicije u rečniku Srpske akademije nauka i umetnosti (SANU) korišćene su za modelovanje različitih tipova definicija (opisnih, gramatičkih, referentnih i sinonimskih) koje imaju različite sintaksičke i leksičke karakteristike. Korpus istraživanja sastoji se od 61.213 definicija imenica, koje su analizirane korišćenjem morfoloških e-rečnika i lokalnih gramatika implementiranih kao pretvarači konačnih stanja u paketu za obradu korpusa otvorenog ...
    ... research, particularly (Barnbrook 2002), analysis of definitions in existing dictionaries and previous research into Serbian (Krstev et al. 2015). 3 Analysis and Recognition of Definitions in the SASA Dictionary The first step in our research was a thorough analysis of various lexical and syntactic features ...
    ... (57%) 24347 (83%) Table 1: The analysis of recognized definitions from the SASA dictionary; the defined word is given in small caps, connected entries are given in bold, while trigger words enabling the connection are given in italic. 4 Corpus Analysis 4.1 Creating a Textbook Corpus For ...
    ... processing suite Unitex. The 21 models developed up to the present moment cover 57% of dictionary definitions, 83% of which were fully recognized. The analysis has shown that many definitions have a structure that can be modelled, as evidenced by the statistics of definitions grouped by type. These models ...

  • Termička zrelost organske supstance i naftno-matični potencijal istočne Hercegovine

    Nikoleta Aleksić (2021)
    Cilj istraživanja, obrade i interpretacije rezultata prikazanih u disertaciji je utvrđivanje termičke zrelosti organske supstance i naftno-matičnog potencijala sedimentnih stena na području istočne Hercegovine, primenom metoda pirolize Rock-Eval, organo-petrografskog proučavanja organske supstance u normalnoj svetlosti i fluorescenciji, koja je pored kvalitativne analize uključila posebno i refleksiju vitrinita. Osim toga, na osnovu organsko-geohemijskih analiza sagledane su karakteristike i poreklo ekstrahovanog bitumena metodom gasne hromatografije - masene spektrometrije, pri čemu su izvršene analize biomarkera kao geohemijskih indikatora. Tokom rada na doktorskoj ...
    organska supstanca, termička zrelost, matične stene, naftni potencijal, refleksija vitrinita, piroliza Rock-Eval, biomarkeri, Karbonatna platforma, istočna Hercegovina

  • Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements

    Filip Miletić, Predrag D. Jovančić, Milos Milovančević, Dragan Ignjatović (2020)
    The capacity of the rotor excavator depends largely on the operation of the subsystem for digging. There is a great contribution to the correct and sharp teeth when the capacity is the highest. In the function of time, the teeth become clogged due to abrasive wear, or changes in their geometric shape. To analyze the bucket wheel drive in depend on wear of the cutting elements in this study adaptive neuro fuzzy inference system (ANFIS) approach was implemented. ANFIS ...
    Pogon rotornog točka, habanje, rezni elementi, ANFIS

  • 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

  • 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

  • Epidotizacija sanidina u kvarclatitima Grota

    Danica Srećković-Batoćanin, Suzana Erić, Nikola Novičić, Nikola Pašajlić, Natalija Batoćanin (2023)
    Propilitska alteracija je veoma česta u gornjokredno-tercijarnim vulkanitima Srbije. Kvarclatiti Grota, otkriveni na dubini od oko 550 m u jednoj od istražnih bušotina su holokristalaste porfirske strukture sa fenokristalima sanidina dimenzija i do 1,5 x 2 cm. Optičkim ispitivanjima su u kvarclatitu potvrdjeni i elementi sitaste, pojkilitske i glomeroporfirske strukture. Kao fenokristali prisutni su sanidin, plagioklas, kvarc, biotit i amfiboli. Sekundarni minerali su hlorit, epidot, coisit, Fe-hidroksidi, redak kalcit i ilit. U fenokristalima sanidina se zapažaju „lepeze“ izduženih kristala ...
    Grot, kvarclatiti, sanidin, epidot

  • Definition of Circulation Conditions and Groundwater Genesis of the Complex Krupaja Hydrogeological Karst System (Eastern Serbia)

    Ljiljana Vasić, Saša Milanović, Tina Dašić (2023)
    Management, Monitoring, Policy and Law,Renewable Energy, Sustainability and the Environment, Geography, Planning and Development, Building and Construction
    ... they infiltrate into the discharge channel of deep thermal water. The physico-chemical characteristics of the groundwater (related to the seasons) of the Krupaja system are shown in Table 1. Table 1. Basic physico-chemical parameters of the Krupaja system. ; Temperature Electrical Dissolved Turbidit: ...
    ... and mean residence times, as well as different responses to recharge, causes the existence of different types of water, in terms of temperature, chemical composition, and age, within the same karst system. In this research, complex investigations of the Krupaja arst system aimed to provide a large ...
    ... hydrochemical characteristics of the water, an increased content of certain trace elements (Al, Fe, Mn, SiO», etc.) was detected, similar to the chemical composition of the water at he natural thermal spring of the Krupaja system [14]. Figure 3 shows in detail the layout of the springs and the borehole ...