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2436 items
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Properties of fly ash and slag from the power plants
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... ro a tica Šešlija et al.: Properties of fly ash and slag from the power plants 319 on the edge of place Kostolac, while PPKO B is located on the northeastern part of the Kostolac coal basin near the village of Drmno (Fig. 1). The Kostolac coal basin, covering an area of 145km2, is lo- cated about ...
... Properties of fly ash and slag from the power plants 321 cium oxide (CaO) are only present in very small quantities. The main reason for the variability of the chemical composi- tion is the waste-rock presence of inorganic composition. Based on the chemical composition the module R is deter- mined, and ...
... this function gave the best correlation results. Results of the correlation coefficient, as a relationship and a correlation sign, are shown in Table 4. Based on analysis of the Table 3. The percentage composition by mass of minerals in the samples of the �y ash and slag. No. the amorphous material ...Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić. "Properties of fly ash and slag from the power plants" in Geologia Croatica, Zagreb : Croatian Geological Survey (2016). https://doi.org/10.4154/gc.2016.26
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Optimisation of underground mine decline development system using genetic algorithm
... (DOT). The heuristic methods used in DOT1 are replaced in the new version of the software tool, DOT2, by a method based on an understanding of exact solutions to a constrained 3-dimensional path problem. Their approach is based on the minimization of the cost of the decline, where the cost is ...
... reproduction process. The selection occurs with a given probability on the base of fitness functions. The fitness function plays a role of the environment to distinguish between good and bad solutions. The recombination is carried out after selection process is finished. It combines, with predefined ...
... are met; 9. Output the best solutions found. In GA the equality and inequality constraints can be treated by different strategies. The penalty function technique is used to transform the constrained optimisation problem to unconstrained optimisation problem by penalizing the constraints and forming ...Zoran Gligorić, Aleksandar Ganić, Rade Tokalić, Aleksandar Milutinović. "Optimisation of underground mine decline development system using genetic algorithm" in Underground mining engineering, Beograd : Univerzitet u Beogradu – Rudarsko–geološki fakultet (2014)
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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 материјалимаDarko Bozovic, Vladimir Simic, Dragan Radulovic, Slobodan Radusinovic, Vesna Matovic, Anja Terzic. "Geochemical evaluation of dolostone deposits in Montenegro: Implications for potential industrial applications" in Science of Sintering, Bor, August 2024, National Library of Serbia (2024). https://doi.org/10.2298/SOS240701029B
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Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites
Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković (2023)To investigate the effect of synthesis procedure and sintering temperature on the functional properties of perovskite/spinel ceramics, BaTiO3/CoFe2O4 composites were prepared by thermal decomposition, coprecipitation, and microemulsion method, and sintered at 1150°C and 1300°C. The phase composition and morphology of as-prepared powders as well as sintered ceramics were thoroughly examined by X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS). The dielectric and ferroelectric measurements were performed in detail. Generally, the ...Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković. "Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites" in Science of Sintering (2023). https://doi.org/10.2298/SOS220512013S
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Утицај обртног магнетног поља на дерацемизацију кристала натријум-хлората
... addition of impurities [3] and temperature changes [4] are some of the methods of deracemization of crystals grown from aqueous solutions. This paper will present the results of the influence of a rotating magnetic field on the deracemization of sodium chlorate crystals from aqueous solutions ...
... (150+9) mT, at the rotational frequency 200- 1200 rpm with a step of 200 rpm. After the growth, which lasted about 4 h, the orientation of the crystals was determined by polarization microscopy. The results show that the rotational frequency of the field affects the fraction of the obtained crystals ...
... Измењено: 2023-10-16 07:52:03 Утицај обртног магнетног поља на дерацемизацију кристала натријум- хлората;Influence of a rotating magnetic field on the deracemization od sodium chlorate crystals М. Милојевић, А. Жекић, П. Дабић, Б. Вучетић, Б. Максимовић Дигитални репозиторијум Рударско-геолошког ...М. Милојевић, А. Жекић, П. Дабић, Б. Вучетић, Б. Максимовић. "Утицај обртног магнетног поља на дерацемизацију кристала натријум-хлората" in XXVII конференција Српског кристалографског друштва, Чачак, 14-15. јун, 2023., Београд : Српско кристалографско друштво (2023)
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Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans
Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović. "Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans" in Carbonates and Evaporites, Springer Science and Business Media LLC (2021). https://doi.org/10.1007/s13146-021-00754-1
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Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans
Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović. "Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans" in Carbonates and Evaporites, Springer Science and Business Media LLC (2022). https://doi.org/10.1007/s13146-021-00754-1
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Adsorption and Polymerization of Aniline on Cu(II)-Montmorillonite: Vibrational Spectroscopy and ab Initio Calculation
Batch adsorption experiments in the presence of oxygen were performed to study the interlayer reactions of aniline on Cu(II)-montmorillonite in aqueous solutions. At concentrations below a critical value of CC ) 2.6 mmol dm-3 only a colored Cu(II)-aniline complex is formed, characterized by a stability constant of log(Kassoc/dm3 mol-1) ) 1.5. At concentrations beyond Cc aniline polymerizes yielding a dark brown product, which is identified by two vibrational spectroscopy techniques, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and ...M. Ilić, E. Koglin, A. Pohlmeier, H. D. Narres, M. J. Schwuger. "Adsorption and Polymerization of Aniline on Cu(II)-Montmorillonite: Vibrational Spectroscopy and ab Initio Calculation" in Langmuir (2000). https://doi.org/ 10.1021/la000534d
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The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector
Natural gas is used for the production of almost 20% of total energy today. The natural gas security of the Republic of Serbia is an urgent strategic, political and security issue. Serbia is one of the most vulnerable countries in Southeast Europe, because it only has one supply route. This study is a contribution to efforts to better understand the factors affecting energy security through the implementation of a new methodology based on the fuzzy–AHP synthesis model for measuring ...... points of the direct line that represent the value of the IEF and the boundaries of the linguistic variables. The normals are drawn through the intersection points to the abscissa on which the membership function (µ) is located and the values of membership are read: µ(A2moderate) = 0.847; µ (A2low) ...
... (35) It is evident, despite the fact that most of the natural gas is placed on the free market, that the domestic natural gas market is highly concentrated with a dominant share of one company. Based on the projections for the development of the natural gas sector, using the historical trend of increasing ...
... is made. The output data of the fuzzy set is defuzzificated throughout the identification procedure. The “best-fit” and “gravity center“ methods are used to identify the output data from the fuzzy composition. Using these methods, the assessment of energy security is expressed depending on the function ...Aleksandar R. Madžarević, Dejan D. Ivezić, Miloš L. Tanasijević, Marija A. Živković. "The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector" in Symmetry, MDPI AG (2020). https://doi.org/10.3390/sym12060908
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An update on the mineral-like Sr-containing transition metal arsenates
Tamara Đorđević, Ljiljana Karanović (2021)We report on the crystal structures of three novel synthetic SrM-arsenates (M = Ni and Fe3+), isostructural or structurally related to the minerals from tsumcorite, carminite and brackebuschite groups. They were synthesised under mild hydrothermal conditions and further characterised using single-crystal X-ray diffraction (SXRD), scanning electron microscopy with energy dispersive spectroscopy (SEMEDS) and Raman spectroscopy. SXRD and SEM-EDS yielded formulae: (I) SrNi2(AsO4)2·2H2O, (II) Sr1.4Fe3+ 1.6(AsO4)2(OH)1.6 and (III) SrFe3+(AsO4)(AsO3OH). All three structures are built up of slightly distorted MO6 octahedra ...арсенати метала, кристална структура, дифракција рендгенских зрака на монокристалима, хидротермална синтеза, Раманова спектроскопија, релевантна једињења у животној средини, арсенeochemistry and PetrologyTamara Đorđević, Ljiljana Karanović. "An update on the mineral-like Sr-containing transition metal arsenates" in Mineralogical Magazine, Mineralogical Society (2021). https://doi.org/10.1180/mgm.2021.41
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Anthropogenic impact on the groundwater regime: Case study of the Velika Morava alluvium
Jovana Mladenović, Vesna Ristić Vakanjac, Milan Kresojević, Boris Vakanjac, Jugoslav Nikolić, Dušan Polomčić, Dragoljub Bajić (2023)The Velika Morava River originates at the junction of the Južna Morava and Zapadna Morava at the town of Stalać in Serbia. It is 185 km long and empties into the Danube. The Velika Morava River Basin occupies a land area of 37 444 km2. The river flows through central Serbia, which features the most fertile land and the highest population density in the country. Public water supply in this region of Serbia relies on groundwater formed in alluvial ...Jovana Mladenović, Vesna Ristić Vakanjac, Milan Kresojević, Boris Vakanjac, Jugoslav Nikolić, Dušan Polomčić, Dragoljub Bajić. "Anthropogenic impact on the groundwater regime: Case study of the Velika Morava alluvium" in National Conference with International Participation “GEOSCIENCES 2023”, Review of the Bulgarian Geological Society, Sofia : Bulgarian Geological Society (2023)
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Laboratory testing of fly ash
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... identified as the product of the reaction system in addition to the ash-water. Its amount is relatively small (below 10 %) and varies depending on several factors: the nature of the fly ash, the type of additive (hydrated lime or cement), the percentage of the additive and partly of the time of exposure ...
... samples. The experiments were done based on the standards that are in use in the European Union. The following mechanical tests have been made: - the compressive strength – uniaxial strength, - the indirect tensile strength – Brazilian experiment, - the modulus of elasticity. The aim of research ...
... that the tests are not carried out on samples of the ash that was previously fragmented, but the patterns of the original particle size distribution, the results are favorable. Compressive strength and tensile strength were tested for samples in S1 and S2, taken from the thermal PPNT A and the results ...Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić. "Laboratory testing of fly ash" in Tehnički vijesnik (2016). https://doi.org/10.17559/TV-20150317171035
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New data concerning the Miocene on the southern slopes of Fruška Gora (northern Serbia): A case study from the Mutalj open pit
Rundić Ljupko, Knežević Slobodan, Vasić Nebojša, Cvetkov Vesna, Rakijaš Milovan. "New data concerning the Miocene on the southern slopes of Fruška Gora (northern Serbia): A case study from the Mutalj open pit" in Geološki anali Balkanskog poluostrva no. 72, Beograd:Rudarsko-geološki fakultet (2011): 71-85. https://doi.org/10.2298/GABP1172071R
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Influence of Post-Synthesis Treatments on the Properties of Brushite/Monetite Powders
Željko Radovanović, Lidija Radovanović, Aleksandar Kremenović, Đorđe Janaćković, Rada Petrović (2022)Dicalcium phosphate (DP) materials, of which brushite and monetite were the most known, have been intensively studied for several decades because of excellent resorptive and osteoconductive properties that can satisfy the requirements needed for various medical applications, such as bone cements, coatings of metallic implants and bone grafts ...Željko Radovanović, Lidija Radovanović, Aleksandar Kremenović, Đorđe Janaćković, Rada Petrović. "Influence of Post-Synthesis Treatments on the Properties of Brushite/Monetite Powders " in Second International Conference on Electron Microscopy of Nanostructures ELMINA 2022, August 22nd–26th, 2022, Belgrade, Serbia, Serbian Academy of Sciences and Arts Knez Mihailova 35, 11000 Belgrade, Serbia (2022)
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Centar za hidrogeologiju karsta - 15 godina nauke i struke
... discussed in the previous text. The traditional eighth CEKA course was held from June 1 to 4, 2021, and the course was followed online by a total of 93 participants from 24 countries around the world. The CEKA course returned to Trebinje in 2022, after a break of four years. Given that the conditions ...
... significantly in the organization of the course. Basic literature was provided by the power point presentations that were regularly distributed to the participants, then the Tutorial, which was also prepared by the members of the Centre, and which was mostly based on the chapters of the book Karst Aquifers ...
... situated in the Dinaric Karst, the locus typicus of karst terrains on the entire planet, as the venue for the course, which was already discussed in the previous chapter by the course initiator. This international course is designed in such a way that, in addition to theoretical lectures on the basic ...urednici Saša Milanović, Ljiljana Vasić, Zoran Stevanović, Branislav Petrović. Centar za hidrogeologiju karsta - 15 godina nauke i struke, Beograd : Univerzitet u Beogradu, Rudarsko-geološki fakultet, Centar za hidrogeologiju karsta, 2023
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Pre-failure deformation monitoring as rockfall prediction tool
... developing joint concept, while the general retreat of the fallen rock mass is expectedly in the upslope direction. The SSE-facing joint set (daylighting on the rock face) and E-facing set sever medium-sized blocks, undercut by the bedding plane (dipping into the mass), causing combined free-fall ...
... and focused on displacement analysis. We acknowledged the individuality of each rock face site and adopted the acquisition accordingly (annual) in respect to our study site. We tried to extract the deformation threshold as exampled in abovementioned case studies and estimate the total vectors ...
... appointing to the block and wedge failure potential. Rock block size and volumes (0.5-2.7 m3) were reported in [9], as well as the first monitoring results and the first rockfall analyses, wherein several detachment zones were distinguished. Further on, these zones were used in the latest published ...Miloš Marjanović, Biljana Abolmasov, Zoran Berisavljević, Marko Pejić, Petko Vranić. "Pre-failure deformation monitoring as rockfall prediction tool" in IOP Conference Series: Earth and Environmental Science, IOP Publishing (2021). https://doi.org/10.1088/1755-1315/833/1/012197
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Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining
Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović (2019)... about the possible expectations regarding the ability of the machine on an annual level, while showing the exact degree of the machine usage by the owner. The parameter work until a general repair (GR) was also an important indicator of the expected functioning of the machine. Based on the data about ...
... advantage of the AHP method is its ability to identify and analyse the inconsistency of the decision-maker in the process of deciding on the priorities in the hierarchal structure. The general schematic display of the AHP method structure is shown in Figure 2. The goal (zero level) of the AHP method structure ...
... Figure 6. The structure of the model in choosing the dozer using the AHP method. The diagram displays abscissa in different colors to show the priority coefficients of the basic parameters (technical, economic, exploitation, survey), grouped according to the dozer type. On the ordinate, the priority ...Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović . "Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining" in Energies, MDPI (2019). https://doi.org/https://doi.org/10.3390/en12122245
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The Newton method for solving nonlinear equations based on aggregation operators
Nebojša M. Ralević, Dejan Ćebić (2019)Nebojša M. Ralević, Dejan Ćebić. "The Newton method for solving nonlinear equations based on aggregation operators" in XLVI International Symposium on Operational Research SYM-OP-IS, Kladovo, 15-18.9.2019, Универзитет у Београду (2019)
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BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1) Composites Synthesized by Thermal Decomposition: Magnetic, Dielectric and Ferroelectric Properties
Marija Šuljagić, Ivan Petronijević, Miljana M. Mirković, Aleksandar Kremenović, Adis Džunuzović, Vladimir B. Pavlović, Aleksandra Kalezić-Glišović, Ljubica Andjelković (2023)To investigate the influence of spinel structure and sintering temperature on the functional properties of BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1), NiFe2O4, ZnFe2O4, and Ni0.5Zn0.5Fe2O4 were in situ prepared by thermal decomposition onto BaTiO3 surface from acetylacetonate precursors. As-prepared powders were additionally sintered at 1150 °C and 1300 °C. X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS) were used for the detailed examination of phase composition and morphology. The magnetic, dielectric, and ...ferroelectric, dielectric properties, magnetic properties, titanate/ferrite composites, phase composition... To overcome the rareness and shortcomings of single- phase magpnetoelectrics, the scientific community has been focused on the development of advanced muhltifunctional composite materials. More specifically, the magnetoelectric coupling, is a consequence of the strain induced on the interface between ...
... consequence of the highest amount of conductive phases since the influence of the spinel phase on dielectric properties is very strong [72]. Further calcination of this sample led to a lower value of the dielectric constant in the same frequency range. The same was observed in the case of BaTiOx ...
... conducted in the electrical field range of 5-40 kV/cm on the Precision Multiferroic Test System with High Voltage Interface (Radiant Technologies, Inc., Albuquerque, New Mexico). 4. Conclusions The aim of this study was the investigation of the effect of phase composition on the magnetic, dielectric ...Marija Šuljagić, Ivan Petronijević, Miljana M. Mirković, Aleksandar Kremenović, Adis Džunuzović, Vladimir B. Pavlović, Aleksandra Kalezić-Glišović, Ljubica Andjelković. "BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1) Composites Synthesized by Thermal Decomposition: Magnetic, Dielectric and Ferroelectric Properties" in Inorganics, MDPI AG (2023). https://doi.org/10.3390/inorganics11020051
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Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example
Miloš Marjanović, Biljana Abolmasov, Igor Peshevski, James Reeves, Irena Georgievska. "Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example" in Understanding and Reducing Landslide Disaster Risk, Springer International Publishing (2020). https://doi.org/10.1007/978-3-030-60227-7_29