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Упит dcterms_subject_txt:chemical analysis

757 items

  • Properties of fly ash and slag from the power plants

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    This paper describes the physical, chemical and mineral properties of ash and slag, which were taken from thermal power plants Nikola Tesla A, Nikola Tesla B, Kostolac A and Kostolac B. The knowledge of the mineralogical material composition is important because the type of minerals directly determines the properties of the fly ash and slag and their possible application. Laboratory tests showed that ash and slag samples consist of the following minerals: amorphous materials, quartz, feldspar, mullite, melilite, cristobalite, ...
    fly ash, slag, physical composition, chemical composition, mineral composition, X-ray diffraction method
    ... Based on the analysis, the fly ash and slag from all four power plants have variable chemical composition. The chemi- cal composition of samples consist mostly of silica (SiO2), then alumina (Al2O3), iron trioxide (Fe2O3), calcium oxide (CaO) and magnesium oxide (MgO), while the chemical elements of ...
    ... equally rep- resented. During the analysis of the results, absolute values of the correlation coefficients are observed in order to achieve easier comparative analysis of the test samples. A significantly large number of dependencies has been achieved with chemical pro- perties, and then with mineral ...
    ... Most of the research is based on an examination of the chemical composition of the ash (THOMAS, 2007; KIM et al., 2005), the mineral ash composi- tion (ŽIVOTIĆ et al., 2015), the mineral ash and coal composition (WARD & FRENCH, 2005) and chemical-mineral ash composi- tion (VASSILEV et al., 2013; VASSILEV ...

  • Kristalografsko proučavanje strukturne desimetrizacije granata grosularsko-andraditske izomorfne serije

    Pavle I. Tančić (2016-09-21)
    U ovoj Doktorskoj disertaciji proučavano je pet različitih zona makroskopski zonarnog grandita sa lokaliteta Meka Presedla (Kopaonik, Srbija). Pomoću hemijske i elektronske analize mikroprobe preračunati su relativno visoko homogeni sastavi zona, t.j.: Grs64±1Adr36±1Sps2 (A), Grs62±1Adr38±1Sps2 (B), Grs59±2Adr40±2Sps2 (C), Grs58±2Adr41±2Sps2 (D) i Grs58±1Adr41±1Sps2 (E). Glavne promene u sastavima izražene formulom: Ca2,93-2,97Mn0,05-0,06Mg0,00-0,01Al1,14-1,26Fe3+0,72-0,83Ti0,00-0,02Si2,97-3,02O12 ukazuju da je jedina značajnija varijacija ustanovljena samo kod Al-Fe3+ raspodela u oktaedarskom položaju. Ovakav hemijski sastav je potvrđen i sa matematičkim proračunima iz IC i Raman analiza. Urađena ...
    Macroscopically zoned grandite, chemical analysis, electron microprobe analysis, Raman, Rietveld, structure, dissymmetrization, space group

  • Laboratory testing of fly ash

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    Fly ash is one of the most common waste materials created by burning of coal. It is composed of smaller particles, consisting mainly of aluminosilicate glass, mullite and quartz, which are collected by electrostatic separators (filter) of gaseous products arising from the combustion of coal. This paper presents the pozzolanic properties, mechanical properties, chemical and mineral composition of fly ash obtained in the combustion process in a power plant Nikola Tesla A (PPNT A) with the addition of a ...
    chemical composition, fly ash, mechanical properties, mineral properties, pozzolanic properties, X-ray diffraction
    ... discussion 3.1 The chemical composition of fly ash Results of chemical analysis of fly ash samples taken in Series 1 (S1) and Series 2 (S2) from PPNT A, are shown in Tab. 7. Table 7 Results of chemical analyses of fly ash taken in S1 and S2 at location of PPNT A Chemical composition S1 S2 ...
    ... (hydrated lime and cement) in a humid environment. 2.2 Chemical composition of fly ash Chemical composition of the fly ash from PPNT A was tested in laboratory for concrete and binders in "Highway Institute A. D.". Chemical analysis was performed on samples with volume of 10 g for "Series ...
    ... of the Serbian Chemical Society. 78, (2013), pp. 725-739. DOI: 10.2298/JSC120716125I [4] SRPS B.H8.359. Methods of analysis of coal and coke - Determination of chemical composition of fuel ash - General requirements. // Belgrade (1973). [5] SRPS B.H8.360. Methods of analysis of coal and coke ...

  • Crystallography and Surface Oxidation of Stoichiometric Arsenopyrite from Šumadija-Kopaonik Pb-Zn/Polymetallic Ore District (Serbia)

    Ivana Jelić, Aleksandar Pačevski, Aleksandar Kremenović, Aleš Šoster, Andreja Šestan, Janez Zavašnik (2023)
    The behaviour and stability of arsenopyrite largely depend on its crystal structure, but studies of crystallography and structural defects are scarce. For clarification, we investigated a series of natural arsenopyrite crystals from the polymetallic Pb-Zn-(±Cu,Ag,Au,Sb,Bi,W) Šumadija-Kopaonik ore district (Serbia) by powder X-ray diffraction (XRPD). Among them, samples from the Drenjak gold mineralisation showed near-stoichiometric FeAsS composition and were further investigated by conventional and high-resolution transmission electron microscopy methods. TEM revealed abundant planar crystallographic defects and epitaxial surface oxide layer ...
    Inorganic Chemistry, Condensed Matter Physics,General Materials Science, General Chemical Engineering, crystal structure, FeAsS, oxidation, TEM, XRPD
    ... e and Co-enriched cobaltite-type enrichment zones [10]. For verification, we investigated the local chemical composition by EDS analysis, which shows coherent, stoichiometric FeAsS chemical composition in both domain types without any deviation compared to the bulk grain. Additionally, the SAED ...
    ... Cu-sulphides [25,26] and were interpreted as an ordered variation of the chemical composition, i.e., the periodic arrangement of impurities. This interpretation cannot be applied to our observations, as the chemical analysis by TEM-EDS shows no variation from the arsenopyrite stoichiometric composition ...
    ... repository. Mendeley Data 2023. [CrossRef] 19. Morimoto, N.; Clark, L.A. Arsenopyrite Crystal-Chemical Relations. Am. Mineral. 1961, 46, 1448—1469. 20. Watanabe, M.; Williams, D.B. The Quantitative Analysis of Thin Specimens: A Review of Progress from the Cliff-Lorimer to the New C-Factor Methods ...

  • Hydrogeochemical approach to estimate the quality of bottled waters in Serbia

    Marina Ćuk, Maja Todorović, Jovana Šisović, Jana Štrbački, Jakov Andrijašević, Petar Papić (2015)
    General Chemical Engineering, General Chemistry

  • Effects of production conditions on the properties of limestone briquettes aimed for acid soil liming

    Vladimir Jovanović, Dragana Nišić, Vladimir Milisavljević, Dejan Todorović, Dragan Radulović, Branislav Ivošević, Sonja Milićević (2022)
    General Chemical Engineering, General Chemistry

  • Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete

    Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović (2021)
    sagorevanje lignita, otpadna šljaka, zamena cementa, proizvodnja maltera i betona, fizičko-mehanička i fizičko-hemijska karakterizacija
    ... were mixed, homogenized and the required amount for analysis was taken by quartering. Portland cement (CEM I 42.5R) was bought from the company CRH Popovac, Serbia. Silica fumes were bought from the company “Sika”. The physical–chemical, chemical and mineralogical composition of the used cement, slag ...
    ... and 90 days. 2.3.3. Physical–chemical Characterization of Hardened Mortar Samples The physical–chemical characterization was performed on hardened mortar samples with maximal possible cement replacement (20%) (P-20M) and included X-Ray-Structural Diffraction Analysis (XRD), infrared spectroscopy (FTIR) ...
    ... hardened mortar samples with maximal possible cement replacement (20%), physical–chemical characterizations were performed and included X-ray and infrared spectrophotometry, scanning electron microscopy, and thermal analysis. Results showed the absence of new phases and the presence of only those which ...

  • Non-Detonating Chemical Mixture for Non-Invasive Methods of Rock Breaking

    Lazar Kričak, Milanka Negovanović, Nikola Simić, Stefan Milanović (2024)
    Within the Innovation developed several different non-detonating chemical mixtures for non-invasive methods of rock breaking. Laboratory and polygon tests gave the satisfactory results and knowledge enough to start the practical experiments in the field. The basis of this innovation is a theoretical assumption that certain chemical mixtures release a large quantity of gases during combustion. If these gases are found in the enclosed space a growing pressure on the walls of the chamber in which combustion takes place will ...
    non-detonating, chemical mixture, rock breaking, borehole pressure

  • Influence of mono- and two-component organic modifiers on determination of lipophilicity of tetradentate Schiff bases

    Nikola Stevanović, Aleksandar Mijatović, Aleksandar Lolić, Mario Zlatović, Rada Baošić (2021)
    The infuences of the application of mono- and two-component organic modifers on lipophilicity determination of 12 tetradentate Schif bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are responsible ...
    Materials Chemistry, Industrial and Manufacturing Engineering, General Chemical Engineering, Biochemistry,General Chemistry

  • Influence of mono- and two-component organic modifiers on determination of lipophilicity of tetradentate Schiff bases

    Nikola Stevanović, Aleksandar Mijatović, Aleksandar Lolić, Mario Zlatović, Rada Baošić (2021)
    The infuences of the application of mono- and two-component organic modifers on lipophilicity determination of 12 tet radentate Schif bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are ...
    Materials Chemistry, Industrial and Manufacturing Engineering, General Chemical Engineering, Biochemistry, General Chemistry

  • Ventex: an expert system for mine ventilation systems analysis

    Nikola Lilić, Ranka Stanković, Ivan Obradović (1997)
    roblems relating to mine ventilation systems analysis are usually of a very complex nature. They involve the estimation of numerous interdependent parameters pertaining to the network status, ventilation status, ventilation system stability, air current losses, climate conditions, gas state, fire risk and dangerous dust pollution risk. The solution to these problems relies, to a great extent, on numerical methods. With the development of computer technology these methods were incorporated as numerical routes in software packages, such as the mine ...
    expert system, mine ventilation

  • Split-Desktop software for the analysis of fragment size distribution of blasted rock mass

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić, Snežana Ignjatović (2023)
    Drobljenje stena je najvažniji pokazatelj u proceni efekata miniranja pri proizvodnom miniranju u površinskoj eksploataciji. Stepen drobljenja stena ima veliki uticaj na efikasnost daljih operacija utovara, transporta, drobljenja i mlevenja. Optimalno drobljenje stena pri proizvodnom miniranju utiče na smanjenje ukupnih troškova proizvodnje. Stoga je pouzdana procena veličine drobljenja odminirane stenske mase veoma važno pitanje, ne samo u operacijama miniranja, već i u rudarskoj proizvodnji. Za predviđanje distribucije veličine komada odminirane stenske mase postoje različiti empirijski modeli. KUZ-RAM model omogućava ...
    Split-Desktop softver, drobljenje stena, miniranje, analiza, digitalna obrada fotografija

  • INVENTS: a hybrid system for subsurface ventilation analysis

    Nikola Lilić, Ranka Stanković, Ivan Obradović (2000)
    Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper we ...
    ... block for the analysis of air flow and pressure distribution in the ventilation network, 2. a block for the analysis of climate conditions in mine chambers, 3. a block for temperature and heat depression analysis in fire incidence conditions, 4. a block for gas distribution analysis in the ventilation ...
    ... planing and design The results obtained after the desired analysis by SimVent can be exported to VENTEX – a diagnostic expert system that performs the analysis of obtained results according to a number of criteria. The result of such an expert analysis is an estimate of the validity and effectiveness of ...
    ... INVENTS: a hybrid system for subsurface ventilation analysis Nikola Lilić, Ranka Stanković, Ivan Obradović Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] INVENTS: a hybrid system for subsurface ventilation analysis | Nikola Lilić, Ranka Stanković, Ivan Obradović ...

  • Size–strain line-broadening analysis of anatase/brookite (TiO<sub>2</sub>)-based nanocomposites with carbon (C): XRPD and Raman spectroscopic analysis

    Aleksandar Kremenović, Mirjana Grujić-Brojčin, Nataša Tomić, Vladimir Lazović, Danica Bajuk-Bogdanović, Jugoslav Krstić, Maja Šćepanović (2022)
    A size-strain line-broadening analysis of the XRPD patterns and Raman spectra for two anatase/brookite (TiO2)-based nanocomposites with carbon (C) was carried out and the results compared with those of a similar sample free of carbon. The crystal structures and microstructures of anatase and brookite, as well as their relative abundance ratio, have been refined from XRPD data by the Rietveld method (the low amount of carbon is neglected). The XRPD size-strain analysis resulted in reliable structure and microstructure results ...
    Materials Chemistry, Metals and Alloys, Atomic and Molecular Physics, Optics, Electronic, Optical and Magnetic Materials

  • INVENTS: A Hybrid Mine Ventilation Planning and Design System

    Lilić Nikola, Stanković Ranka, Obradović Ivan (2013)
    Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper we ...
    hybrid systems, mine ventilation, expert systems
    ... block for the analysis of air flow and pressure distribution in the ventilation network, 2. a block for the analysis of climate conditions in mine chambers, 3. a block for temperature and heat depression analysis in fire incidence conditions, 4. a block for gas distribution analysis in the ventilation ...
    ... planing and design The results obtained after the desired analysis by SimVent can be exported to VENTEX – a diagnostic expert system that performs the analysis of obtained results according to a number of criteria. The result of such an expert analysis is an estimate of the validity and effectiveness of ...
    ... Faculty of Mining and Geology, University of Belgrade, Djusina 7, 11.000 Belgrade Abstract: Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full und ...

  • Rock slope stability analysis under Hoek–Brown failure criterion with different flow rules

    Svetlana Melentijević, Zoran Berisavljević, Dušan Berisavljević, Claudio Olalla Marañón (2024)
    The stability analysis of homogeneous rock slope following the Hoek–Brown failure criterion under the hypothesis of different flow rules is performed based on limit equilibrium and finite element methods. The applied failure criterion is the generalized Hoek–Brown that can be introduced as a shear/normal function in analysis applying different flow rules. The results are compared with those obtained by the application of equivalent shear strength parameters of the Mohr–Coulomb criterion, considering that this is still the most widely used ...
    Kružna klizna površ, Huk-Braunov kriterijum loma, Kriterijum popuštanja, Smičuća/normalna funkcija, Nivo napona, Verovatnoća i parametarska analiza

  • Значај петрографске анализе флуидних инклузија

    Стефан Петровић, Милош Велојић (2022)
    У раду је истакнут значај петрографске анализе током истраживања флуидних инклузија и приказане могућности ове методе на примерима неких од карактеристичних петрографских појава из различитих минерала. Петрографска анализа је први корак у испитивању флуидних инклузија. Правилно спроведена, петрографска анализа омогућава одређивање генетске везе флуидних инклузија и минерала домаћина, препознавање карактеристика флуидних инклузија и релевантну интерпретацију података из наредних корака истраживања. Петрографском анализом се дефинишу: а) дистрибуција флуидних инклузија у минералу; б) облик, величина и фазни састав флуидних инклузија; в) групације ...
    петрографија, флуидне инклузије, флуиди, групације

  • Advancing Sentiment Analysis in Serbian Literature: A Zero and Few-Shot Learning Approach Using the Mistral Model

    Milica Ikonić Nešić, Saša Petalinkar, Mihailo Škorić, Ranka Stanković, Biljana Rujević (2024)
    Ova studija predstavlja analizu sentimenta srpskih starih romana iz perioda 1840-1920, koristeći veliki jezički model (LLM) Mistral za tehniku učenja sa zasnovani na takozvanim "zero" i "few-shot" pokušajima. Glavni pristup uvodi inovacije osmišljavanjem istraživačkih upita (promptova) uključuju tekst sa uputstvom za klasifikaciju bez primera i na osnovu nekoliko primera, omogućavajući jezičkom modelu da klasifikuje osećanja u pozitivne, negativne ili objektivne kategorije. Ova metodologija ima za cilj da pojednostavi analizu osećanja ograničavanjem odgovora, čime se povećava preciznost ...
    zero-shot, few-shot, sentiment, Serbian, Mistral model

  • Sentiment Analysis of Serbian Old Novels

    Ranka Stanković, Miloš Košprdić, Milica Ikonić Nešić, Tijana Radović (2022)
    In this paper we present first study of Sentiment Analysis (SA) of Serbian novels from the 1840-1920 period. The preparation of sentiment lexicon was based on three existing lexicons: NRC, AFFIN and Bing with additional extensive corrections. The first phase of dataset refinement included filtering the word that are not found in Serbian morphological dictionary and in second automatic POS tagging and lemma were manually corrected. The polarity lexicon was extracted and transformed into ontolex-lemon and published as initial ...
    sentiment lexicon, sentiment analysis, distant-reading, machine learning, old novels

  • Optimization and Analysis of Drilling and Blasting Parameters Using O-Pitblast Software

    Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić (2024)
    The development of modern technologies has enabled the application of specialized softwares in the field of mining through various segments and processes, including in works related to drilling and blasting. The application of specialized software for drilling and blasting with the use of modern technologies such as photogrammetry enabled more accurate data from the field for later processing. By processing data and creating a 3D model of the terrain for drilling and blasting works, it can obtain precise data, ...
    optimizacija, 3D model, bušenje, miniranje, O-Pitblast, softver