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264 items
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The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers
One of the most important prerequisites for the successful operation of the open-cast lignite mine is to carry out all the auxiliary works timely with the necessary quality. The most important and most commonly used auxiliary machines are bulldozers. Engaging time of bulldozers use is in direct relation with the coefficients of the time and capacity utilization of the continuous system for the excavation of coal and tailings, which indicates their importance. More than 100 bulldozers have been hired ...... during which the mechanization is in functional condition, meaning it is used [2, 5]. Life cycle of a machine, facility or any other technical system has a complex structure, and it encompasses several distinctive but interrelated and timely adjusted groups of activities. Technical system is used ...Dragan Ignjatović, Predrag Jovančić, Stevan Đenadić, Ivan Janković, Ivica Ristović. "The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers" in 7th International Symposium Mining and Environmental Protection, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2019)
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Determination of Mechanical Properties of Altered Dacite by Laboratory Methods
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 ...... 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 UCS of the rock material, and mi) with an increase in the participation ...
... 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 UCS of the rock material, and m;) with an increase in the participation ...
... procedure, monolithic rock material (100% D and 100% AD) specimens and discs of rock material were prepared. Discs of rock material were used to form groups of composite specimens that contained 10%, 30%, 50%, and 70% volumetric participation of weaker material (altered dacite) (Figure 4). It is essential ...Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović. "Determination of Mechanical Properties of Altered Dacite by Laboratory Methods" in Minerals, MDPI AG (2021). https://doi.org/10.3390/min11080813
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Joint interpretation of paleomagnetic, structural and AMS results from the Vardar Zone of Serbia
Emo Marton, Marinko Toljić, Vesna Lesić, Vesna Cvetkov. "Joint interpretation of paleomagnetic, structural and AMS results from the Vardar Zone of Serbia" in 18th Meeting of the Central European Tectonic Studies Group (CETEG) & 25th Meeting of the Czech Tectonic Studies Group, 22-25th April, 2021, Terchová, Slovakia, Department of Geological Sciences, Masaryk University in cooperation with the Czech Geological Survey, IPE MU Brno and UK Praha (2021)
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The shear strength evaluation of rough and infilled joints and its indications for stability of rock cutting in schist rock mass
Construction of E75 highway section through Grdelica gorge was one of the most demanding projects realized in recent Serbian history. The alignment approximately 25 km long consists of several tens of bridges, two tunnels, three galleries and cuts with total length of 6 km. The alignment passes through highly anisotropic Palaeozoic schist rock formation of different weathering grades. This study focuses on shear strength properties of discontinuities, which are found to be the critical feature contributing to the occurrence ...Dušan Berisavljević, Zoran Berisavljević, Svetlana Melentijević. "The shear strength evaluation of rough and infilled joints and its indications for stability of rock cutting in schist rock mass" in Bulletin of engineering geology and the environment, Springer (2022). https://doi.org/10.1007/s10064-022-02580-8
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Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization
Maja Todorović, Jana Štrbački, Marina Ćuk, Jakov Andrijašević, Jovana Šišović, Petar Papić . "Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization" in Mineral and Thermal Waters of Southeastern Europe, Springer International Publishing (2016). https://doi.org/10.1007/978-3-319-25379-4
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Crystal structure of K3EuSi2O7
alkalni silikati elemenata retkih zemalja, kristalna struktura, sinteza metodom fluksa, rendgenska difrakcija na monokristalu... are parallel to the (001) plane: (I) octahedral layers and (II) sorosilicate layers, formed by a mixture of Si2O7–groups and K2O6+3 polyhedra (Fig. 3.). Fig. 2. The Si2O7 groups and EuO6 polyhedra (octahedra: OC-6; trigonal prisms: TPR-6) in the crystal structure of K3EuSi2O7 oriented approximately ...
... 2.334 (7) Å. Each Eu1O6 octahedron (OC-6) shares its six corners with six different Si2O7 groups, while each Er2O6 trigonal prism (TPR-6) also shares six corners, but with only three different Si2O7 groups. Each Si2O7 group is connected to five different cations, i.e. four Eu1 and one Eu2. The ...
... a slightly distorted octahedral coordination and the other part are in an ideal trigonal prismatic coordination environment. The disilicate Si2O7 groups connect four EuO6 octahedra and one EuO6 trigonal prism. Three differently coordinated potassium cations are located between them. Silicates containing ...Sabina Kovač, Predrag Dabić, Aleksandar Kremenović. "Crystal structure of K3EuSi2O7" in Journal of the Serbian Chemical Society, National Library of Serbia (2021). https://doi.org/10.2298/JSC210218026K
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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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Old or New, We Repair, Adjust and Alter (Texts)
Cvetana Krstev, Ranka Stanković (2020)U ovom radu predstavljamo kako se e-rečnici i kaskade transduktora konačnih stanja implementirani u alatu Unitex mogu koristiti za rešavanje tri problema transformacije teksta: ispravljanje tekstova nakon OCR-a, vraćanje dijakritičkih znakova i prebacivanje između različitih jezičkih varijanti.ispravka teksta, OCR greške, restauracija dijakritika , jezičke varijante, elektronski rečnik, transduktori konačnih stanja... removed; for instance, zbog toga sto ‘because of that’ ⇒ zbog toga što, thus avoiding multiple candidates for sto (sto ‘table/hundred’ and što, a functional word that can be an adverb, a pronoun or a conjunc- tion); – A list of 50 most frequent bigrams obtained from the SrpKor in which at least one word ...
... ignorance) or machines during transmission and storage (Peterson, 1980). Peterson, as many other authors, classifies typographic errors into four groups: insertions, deletions, replacements and reversals. However, texts pro- duced by humans can also be mutilated in other ways: for many reasons, when ...
... users (underlying, redactor’s marks, comments, etc.). OCR errors that occur in scanned texts differ from typing errors, which can be divided into two groups, typographic errors that are the result of mistypes and cognitive errors caused by a misunderstanding of the correct spelling of a word (Kukich, 1992) ...Cvetana Krstev, Ranka Stanković. "Old or New, We Repair, Adjust and Alter (Texts)" in Infotheca, Faculty of Philology, University of Belgrade (2020). https://doi.org/10.18485/infotheca.2019.19.2.3
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Overcoming the Low Oral Bioavailability of Deuterated Pyrazoloquinolinone Ligand DK-I-60-3 by Nanonization: A Knowledge-Based Approach
Jelena R. Mitrović , Branka Divović-Matović, Daniel E. Knutson, Jelena B. Ðoković, Aleksandar Kremenović, Vladimir D. Dobričić, Danijela V. Randjelović, Ivana Pantelić, James M. Cook, Miroslav M. Savić, Snežana D. Savić (2021)Poor water solubility of new chemical entities is considered as one of the main obstacles in drug development, as it usually leads to low bioavailability after administration. To overcome these problems, the selection of the appropriate formulation technology needs to be based on the physicochemical properties of the drug and introduced in the early stages of drug research. One example of the new potential drug substance with poor solubility is DK-I-60-3, deuterated pyrazoloquinolinone, designed for the treatment of various neuropsychiatric ...... DK-I-60-3 was comparable to the solubility of monodeuterated analog DK-I-56-1 (Table 2) [13]. As expected, because of the absence of ionizable functional groups (Figure 1b), the solubility did not change under different pH conditions. Furthermore, solubility in oils was low, excluding the lipid formulations ...
... molecules on the particle surface moves the shear plane to a longer distance, resulting in lower zeta potential [20]. When the polymer concentration is low, the particle surface is not densely covered by the polymer, and the anionic surfactant can more easily reach the surface of the nanocrystal. Consequently ...
... differences. Calculated total AUC in the groups of animals in the fed state was 1.5 times Pharmaceutics 2021, 13, 1188 15 of 19 higher compared to total AUC in fasted state animals, probably because of the smaller elimination rate. On the other hand, in both groups of animals that received nanocrystal ...Jelena R. Mitrović , Branka Divović-Matović, Daniel E. Knutson, Jelena B. Ðoković, Aleksandar Kremenović, Vladimir D. Dobričić, Danijela V. Randjelović, Ivana Pantelić, James M. Cook, Miroslav M. Savić, Snežana D. Savić. "Overcoming the Low Oral Bioavailability of Deuterated Pyrazoloquinolinone Ligand DK-I-60-3 by Nanonization: A Knowledge-Based Approach" in Pharmaceutics, MDPI, Basel, Switzerland (2021). https://doi.org/10.3390/pharmaceutics13081188
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In vitro and in silico study of the biological activity of tetradentate Schiff base copper(II) complexes with ethylenediamine-bridge
Aleksandar Mijatović, Nevenka Gligorijević, Dušan Ćoćić, Snežana Spasić, Aleksandar Lolić, Sandra Aranđelović, Milan Nikolić, Rada Baošić (2023)The biological activity of six structurally similar tetradentate Schiff base copper(II) complexes, namely [Cu(ethylenediamine-bis-acetylacetonate)] (CuAA) and five derivatives where two methyl groups are replaced by phenyl, (CuPP), CF3 (CuTT) or by mixed groups CH3/CF3 (CuAT), Ph/CF3 (CuPT), and Ph/CH3 (CuAP) has been investigated. The set of antioxidant assays was performed, and the results were expressed as IC50 and EC50 values. The series of complexes showed interesting bioactivity and were investigated for the determination of antioxidant, antifungal, antimicrobial, and cytotoxic ...Aleksandar Mijatović, Nevenka Gligorijević, Dušan Ćoćić, Snežana Spasić, Aleksandar Lolić, Sandra Aranđelović, Milan Nikolić, Rada Baošić. "In vitro and in silico study of the biological activity of tetradentate Schiff base copper(II) complexes with ethylenediamine-bridge" in Journal of Inorganic Biochemistry, Elsevier BV (2023). https://doi.org/10.1016/j.jinorgbio.2023.112224
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In vitro and in silico study of the biological activity of tetradentate Schiff base copper(II) complexes with ethylenediamine-bridge
Aleksandar Mijatović, Nevenka Gligorijević, Dušan Ćoćić, Snežana Spasić, Aleksandar Lolić, Sandra Aranđelović, Milan Nikolić, Rada Baošić (2023)The biological activity of six structurally similar tetradentate Schiff base copper(II) complexes, namely [Cu (ethylenediamine-bis-acetylacetonate)] (CuAA) and five derivatives where two methyl groups are replaced by phenyl, (CuPP), CF3 (CuTT) or by mixed groups CH3/CF3 (CuAT), Ph/CF3 (CuPT), and Ph/CH3 (CuAP) has been investigated. The set of antioxidant assays was performed, and the results were expressed as IC50 and EC50 values. The series of complexes showed interesting bioactivity and were investigated for the determination of antioxidant, antifungal, antimicrobial, and ...Aleksandar Mijatović, Nevenka Gligorijević, Dušan Ćoćić, Snežana Spasić, Aleksandar Lolić, Sandra Aranđelović, Milan Nikolić, Rada Baošić. "In vitro and in silico study of the biological activity of tetradentate Schiff base copper(II) complexes with ethylenediamine-bridge" in Journal of Inorganic Biochemistry, Elsevier BV (2023). https://doi.org/10.1016/j.jinorgbio.2023.112224
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Agates of the Lece Volcanic Complex (Serbia): Mineralogical and Geochemical Characteristics
Agate veins and nodules occur in the Lece Volcanic Complex (Oligocene-Miocene) situated in the south of Serbia and occupying an area of 700 km2. This volcanic complex is composed predominantly of andesites, with sporadic occurrences of andesite-basalts, dacites and latites, and features agate formations that have been very little investigated. This study focuses on five selected agate occurrences within the Lece Volcanic Complex, employing optical microscopy, scanning electron microscopy (SEM), X-ray powder diffraction analysis, inductively coupled plasma mass spectrometry ...Zoran Miladinović, Vladimir Simić, Nenad Nikolić, Nataša Jović Orsini, Milena Rosić. "Agates of the Lece Volcanic Complex (Serbia): Mineralogical and Geochemical Characteristics" in Minerals, MDPI AG (2024). https://doi.org/10.3390/min14050511
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Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry
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 revitalizationSteven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti. "Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry" in SSRN Electronic Journal, Elsevier BV (2021). https://doi.org/10.2139/ssrn.3945979
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Determining seismic hazard in slowly deforming region: Can we gather enough information from karst caves?
Ana Mladenović, Jelena Ćalić (2021)Methods to determine seismic hazard in any region vary depending on the regional seismicity, but can be roughly grouped into two main groups: one based on probabilistic methods that use data about known seismicity in the region, and another, which is based on data related to the faulting processes and determination of seismically active faults. Both groups of methods are relatively good for seismically active regions. However, in regions of low seismic activity and slow deformations, there is neither ...Ana Mladenović, Jelena Ćalić. "Determining seismic hazard in slowly deforming region: Can we gather enough information from karst caves?" in EGU General Assembly 2021, European Geosciences Union (2021). https://doi.org/10.5194/egusphere-egu21-8723
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Low-temperature phase transition and magnetic properties of K3YbSi2O7
Predrag Dabić, Volker Kahlenberg, Biljana Krüger, Marko Rodić, Sabina Kovač, Jovan Blanuša, Zvonko Jagličić, Ljiljana Karanović, Václav Petříček, Aleksandar Kremenović (2021)alkalni silikati elemenata retkih zemalja, fazni prelazi, magnetne karakteristike, razdvajanje kristalnog polja, silikati lantanica... (f) form sorosilicate layers sharing common vertices and edges with the Si,O,7 groups, respectively. Atoms are shown as spheres using the following colour code: Yb: turquoise, Si: blue, K: violet, O: red. The Si,O7 groups represent isolated units formed by two SiO, tetrahedra which share one vertex [Figs ...
... polyhedra and tetrahedra of the Si2O7 groups in �-K3YbSi2O7. Bridging O atoms define an Si—O—Si angle of 180� (a, c). �0-K3YbSi2O7: monocapped trigonal prismatic K2O6+1 coordination polyhedra are formed as a result of a coupled tilting of the tetrahedra in the Si2O7 groups. Consequently, the bridging O atoms ...
... polyhedra and tetrahedra of the Si,07 groups in 6-K3;YbSi,O7. Bridging O atoms define an Si—O—Si angle of 180° (a, c). B’-K3YbSi,07: monocapped trigonal prismatic K20.¢,; coordination polyhedra are formed as a result of a coupled tilting of the tetrahedra in the Si,O, groups. Consequently, the bridging O atoms ...Predrag Dabić, Volker Kahlenberg, Biljana Krüger, Marko Rodić, Sabina Kovač, Jovan Blanuša, Zvonko Jagličić, Ljiljana Karanović, Václav Petříček, Aleksandar Kremenović. "Low-temperature phase transition and magnetic properties of K3YbSi2O7" in Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials, International Union of Crystallography (IUCr) (2021). https://doi.org/10.1107/S2052520621006077
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Stability analysis on slope PK dacite Ceramide
Safe surface mining exploitation of minerals is possibile only if stable bench and overall slopes in the open pit are construct. In order to to construct stable open pit slopes, it is necessary to carry out certain physical and mechanical laboratry testing of mineral raw materials in order to determine the geomechnical calculating parameters. These calculating parameters represent the base ground for performing slopes analyses and the open pit design. In this paper, an stability analysis of benches and ...Vladimir Čebašek, Veljko Rupar, Vladimir Ivoš, Vladimir Petković. "Stability analysis on slope PK dacite Ceramide" in VIII International geomechanics conference, Scientific And Technical Union of Mining, Geology and Metallurgy (2018)
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Determining seismic hazard in slowly deforming region: Can we gather enough information from karst caves?
Ана Младеновић, Јелена Ћалић (2021)... time during which these geological units have been exposed on the surface,led to intensive karst process and formation of both surface and underground karst forms.Therefore, investigations of faults and deformations on the field surface are very difficult, butinvestigations of neotectonically active faults ...
... butcan be roughly grouped into two main groups: one based on probabilistic methods that use dataabout known seismicity in the region, and another, which is based on data related to the faultingprocesses and determination of seismically active faults. Both groups of methods are relativelygood for seismically ...Ана Младеновић, Јелена Ћалић. "Determining seismic hazard in slowly deforming region: Can we gather enough information from karst caves?" in EGU General Assembly 2021, European Geosciences Union (2021). https://doi.org/10.5194/egusphere-egu21-8723
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Contribution to the geotechnical classification of municipal waste landfills in Serbia
Management, Monitoring, Policy and Law, Nature and Landscape Conservation, Geochemistry and Petrology, Waste Management and Disposal,Geotechnical Engineering and Engineering Geology,Water Science and Technology,Environmental Chemistry,Environmental EngineeringDragoslav Rakić, Irena Basarić, Laslo Čaki, Slobodan Ćorić. "Contribution to the geotechnical classification of municipal waste landfills in Serbia" in Environmental Geotechnics, Thomas Telford Ltd. (2018). https://doi.org/10.1680/jenge.18.00028
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Polymorphism and photoluminescence properties of K3ErSi2O7
alkalni silikati elemenata retkih zemalja, silikati lantanoida, polimorfizam, fotoluminescencija, kristalna strukturaPredrag Dabić, Marko G. Nikolić, Sabina Kovač, Aleksandar Kremenović. "Polymorphism and photoluminescence properties of K3ErSi2O7" in Acta Crystallographica Section C Structural Chemistry, International Union of Crystallography (IUCr) (2019). https://doi.org/10.1107/S2053229619011926
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Утицај похабаности резних елемената роторног багера на ниво вибрација погона за копање
Филип Милетић (2023)У докторској дисертацији је анализиран утицај похабаности резних елемената роторног багера на потрошњу електричне енергије и ниво амплитуде вибрација погона за копање. Креиран је модел који у функцији стања резних елемената дефинише зависност разматраних физичких феномена. За развој модела примењене су једначине теорије осцилација и Ватметарска метода [1] којом се одређује потрошња електричне енергије. За верификацију модела извршена су мерења на роторном багеру SRs2000.32/5+VR ангажованом на откопавању откривке на површинском копу Тамнава–Западно поље. Обављено је пет мерења. Резни елементи су ...Филип Милетић. Утицај похабаности резних елемената роторног багера на ниво вибрација погона за копање, Београд : [Ф. Милетић], 2023