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Упит dcterms_subject_txt:solid mineral raw materials

705 items

  • Optimizacija parametara reza rotornog bagera pri otkopavanju materijala sa povećanom čvrstoćom

    Saša D. Bošković (2016-09-09)
    Otkopavanje materijala rotornim bagerom je veoma sloţen fiziĉko-mehaniĉki proces. Pokazatelji efektivnosti tog procesa zavise od velikog broja raznovrsnih ĉinilaca od kojih se posebno mogu istaći: fiziĉko-mehaniĉke karakteristike materijala koji se otkopava, reţim rada bagera i izbor tehnoloških parametara bloka, odreska i reza, geometrije vedrica i zuba itd. Poseban problem se javlja kod otkopavanja materijala povećane ĉvrstoće, što je ĉest sluĉaj na našim površinskim kopovima. Dimenzionisanje specifiĉne sile kopanja bagera prema manjim masama izuzetno ĉvrstog materijala je neracionalno i rešenje ...
    rotorni bager, parametri reza, otpor na kopanje, dinamika bagera, kapacitet, optimizacija, specifična potrošnja energije
    ... dok je istovremeno sadrţaj silicijum dioksida nizak i iznosi samo 2% do 6%. Prisustvo ovog minerala je i glavni uzroĉnik habanju alata za rezanje. Tabela 2.5. Mineralni sastav ispitivanih uzoraka Mineral Uzorak/Sadrţaj (%) Prosek 1 2 3 4 5 SiO2 4,02 6,19 2,20 1,57 3,80 3,56 Al2O3 3,64 2,46 ...
    ... parametara reza rotornog bagera pri otkopavanju materijala sa povećanom čvrstoćom;Optimization of bucket wheel excavator cutting parameters at mining of materials with increased strength Saša D. Bošković Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Optimizacija ...
    ... parametara reza rotornog bagera pri otkopavanju materijala sa povećanom čvrstoćom;Optimization of bucket wheel excavator cutting parameters at mining of materials with increased strength | Saša D. Bošković | Универзитет у Београду | 2016-09-09 | | http://dr.rgf.bg.ac.rs/s/repo/item/0004054 Дигитални репозиторијум ...

  • Макроскопско препознавање стена - практикум

    Кристина Шарић, Владица Цветковић (2021)
    петрологија, стене

  • Metode ispitivanja sedimentnih stena

    Vesna Matović, Violeta Gajić, Nebojša Vasić (2019)
    sedimentne stene, ispitivanje

  • Three new Sr-bearing arsenates, hydrothermally synthesized in the system SrO–MO–As2O5–H2O (M2+ = Mg, Cu, Zn)

    Tamara Đorđević, Ljiljana Karanović (2018)
    During systematic research on the mineral-related synthetic arsenates, with particular focus on their structural and spectroscopic classification, three new Sr-containing arsenates Sr2Mg(AsO4)2· 2H2O (1), Sr2Zn4(AsO4)4·H2O (2) and Sr2Cu7(AsO4)6 (3) have been synthesized under low-temperature hydrothermal conditions in the system SrO MO As2O5 H2O (M 2þ = Mg, Zn, Cu). Their crystal structures were determined using room-temperature single-crystal X-ray diffraction data and refined to the following R-values: 1– R1 = 0.025; 2– R1 = 0.030; 3– R1 = 0.035. Compounds ...
    стронцијум, арсен, арсенати, кристална структура, дифракција рендгенских зрака на монокристалима, хидротермална синтеза, Раманска спектроскопија

  • Phase and microstructural study of urinary stones

    Miljana Mirković, Anja Dosen, Suzana Erić, Predrag Vulić, Branko Matović, Aleksandra Rosić (2019)
    In this paper we present the phase and morphological characteristics of urinary stones from Serbian patients. The study included for the first time the determination of the phase composition and a statistical analysis of the presence of different types of urinary stones in both men and women in Serbia. The main goal of study was representation of collected data for the first time. For past three years, more than 600 samples were collected from Serbian patients. The phase composition ...
    бубрежно камење, фазни састав, статистика, рендгенска дифракција праха, скенирајућа електронска микроскопија

  • Filling of dolines with aeolian sediments in the high-mountain karst of the Dinarides (Mt. Durmitor, Montenegro)

    Mirela Djurović, Violeta Gajić, Predrag Djurović (2022)
    Filling of dolines with aeolian sediments, one of the less frequently described ways in which they are filled, is analysed in the present study on an example of a doline in the high-mountain karst of the Dinarides. There is a series of deep dolines on a broad ridge (about 2450 m a.s.l.) on Mt. Durmitor (Montenegro) in the southeastern part of the Dinarides. The accumulation of very fine-grained sand that almost completely fills one of the dolines was analysed. ...
    Doline, Zapuna, Eolski sedimenti, Karst, Dinaridi, Crna Gora

  • Adsorption and Polymerization of Aniline on Cu(II)-Montmorillonite:  Vibrational Spectroscopy and ab Initio Calculation

    M. Ilić, E. Koglin, A. Pohlmeier, H. D. Narres, M. J. Schwuger (2000)
    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 ...
    Анилин, адсорпција, полимеризација, Cu(II)-Монтморилонит, ФТИР, аб инитио прорачун

  • Substitution reactions of some novel sterically hindered monofunctional Pd(II) complexes

    Aleksandar Mijatović, Jovana Bogojeski, Biljana Petrović, Živadin D. Bugarčić (2011)
    Reakcije supstitucije monofunkcionalnih kompleksa [(TLtBu)PdCl]+ i [Pd(tpdm)Cl]+, gde je TLtBu = 2,6-bis[(1,3-di-terc-butilimidazolin-2-imino)metil]piridin i tpdm = terpiridindimetan, sa nukleofilima kao što su: tiourea, I−, Br−, NO2−, piridin i dimetil-sulfoksid (DMSO) proučavani su u 0,1 M vodenom rastvoru NaClO4 u prisustvu 10 mM NaCl. Reakcije su sprovedene na tri različite temperature (288, 298 i 308 K) korišćenjem tehnike zaustavljenog protoka na različitim temperaturama. Reakcije supstitucije su praćene pod uslovima pseudo prvog reda sa velikim viškom nukleofila. Dobijeni rezultati pokazuju da kompleks ...
    Materials Chemistry, Inorganic Chemistry, Physical and Theoretical Chemistry
    ... nucleophiles (Fig. 1) in 0.1 M NaClO4 aqueous solution and in the presence of 10 mM NaCl to prevent spontaneously hydrolysis. 2. Experimental 2.1. Materials and methods The ligands thiourea (Kemika, Zagreb), NaI, KBr, NaNO2, pyridine (Zorka, Šabac) dimethylsulfoxide (DMSO) (Fluka)wereusedwithout further ...
    ... nucleophiles (Fig. 1) in 0.1 M NaClO,4 aqueous solution and in the presence of 10 mM NaCl to prevent spontaneously hydrolysis. 2. Experimental 2.1. Materials and methods The ligands thiourea (Kemika, Zagreb), Nal, KBr, NaNOz, pyridine (Zorka, Sabac) dimethylsulfoxide (DMSO) (Fluka) were used without further ...

  • Exhumation history of the Juhor Mts. in central Serbia, the Northern Serbo–Macedonian Subunit

    Uros Stojadinovic, Hannah Pomella, Nemanja Krstekanić, Bojan Kostić, Maja Maleš, Nikola Randjelovic, Miloš Radonjić (2024)
    Northern Serbo–Macedonian Subunit, low-t thermochronology, kinematic analyses, extensional deformations

  • Damage quantification of built stone on Dark Gate (Belgrade, Serbia): sample of damage index application for decay rate evaluation

    Maja Franković, Nevenka Novaković, Vesna Matović (2015)
    The Dark Gate is the monument of culture, part of the cultural and historical complex of the Belgrade Fortress. It is constructed of limestone blocks that after 270 years of exposure to environmental conditions and different anthropogenic influences show wide ranges of decay forms. During 2007, detail registration of all built limestone microfacies and weathering forms was done using tools of monument mapping. A correlation scheme ‘‘intensity– damage category’’ was made according to the type, intensity, and distribution of ...
    Krečnjak, mapiranje, Indeks raspadanja, brzina raspadanja, progresija
    ... features, it is evident that algal rudstone microfacies are characterized by loss of stone materials in forms of surface recession and outburst, while grainstone microfacies is marked by relief loss of stone materials and detachment of crust following by granular disintegration and flaking. If we compare ...
    ... wetting-drying and freeze-thaw caused continual increas- ing intensities of decay and very heavy damage in different forms of loss of stone materials (surface recession, relief, and outburst). The present state of the gate is result of the complex action of the above-mentioned natural factors ...
    ... et al (2002) Stone consolidants: brethane — a report of an 18-year review of brethane-treated sites. In: Fidler J (ed) Stone: stone building materials, construction, and associated component systems: their decay and treatment, english heritage research transactions. 2. James & James, London ...

  • Distribution of Uranium and Rare Elements in Radioactive Phosphate-Bearing Anomalies in Southeast Mongolia

    Boris Vakanjac, Neil Rutherford, Vesna Ristić Vakanjac, Tanita Đumić, Suzana Đorđević Milošević (2020)
    Soviet and Mongolian geologists initiated geological exploration of Mongolia for minerals after World War II (1945). These activities lasted until the breakup of the USSR in 1991. As part of this exploration systematic uranium and rare element exploration was undertaken across Mongolia. New exploration resumed in Mongolia at the beginning of the 21st century for a range of ore and mineral deposit styles including uranium, coal, base and precious metals and Fe-ore. This was generally undertaken by Western-based companies. This ...
    uran, radioaktivnost, kreda, retki elementi, fosfati, anomalije, Dornogobi

  • Evidence of Variscan and Alpine tectonics in the structural and thermochronological record of the central Serbo-Macedonian Massif (south-eastern Serbia)

    Milorad D. Antić, Alexandre Kounov, Branislav Trivić, Richard Spikings, Andreas Wetzel (2016)
    General Earth and Planetary Sciences
    ... Umin N=19 imylonitc • lneadon N shear-zone % foliation foliation outside" % ihe shear:zone - Vranjska Banja area - see Figure 8 • Mineral lineation • bi-afold axis of Fa = byi-afold axis of F+ + bi- afold axis of F, Southern part of the Lmin Lower Caomplex N=6 Fig.4 Lower ...
    ... O 42 *% 0' N || ~ N y j }a ~ AOI NM / i w\ S 1673 “ Outcrop-scale high conf. “ Outcrop-scale low conf. m Microstructure s Mineral lineation elongate ribbons of quartz, plunges gently in north-west- south-east direction (Ly, in Fig. 4b). The fold axes b, of large recumbent ...
    ... Unit, although they show evidence of higher metamorphic grade than the greenschist facies typical for the Vlasina Unit (Babović et al. 1977). Mineral assemblages in Vranjska Banja area showing the peak metamorphic conditions of 530-585 "C at 5.2–6.1 kbar (0.52-0.61 GPa, i.e. the bound- ary ...

  • Distribution of Potentially Toxic Elements in the City of Zintan and Its Surroundings (Northwestern Libya) by Surface Soil Sampling

    Boris Vakanjac, Zorana Naunović, Vesna Ristić Vakanjac, Tanita Đumić, Saša Bakrač, Jana Štrbački, Vuk Gajić, Taher Mohamed Alzarog (2023)
    The study area is the city of Zintan, in northwestern Libya, which has grown over the past 30 years. Its current population is roughly 30,000. Although the city is in part commercial, most of the population engages in agriculture and primarily grows cereal crops (wheat and barley). The demand of the growing city for agricultural products has increased, intensifying the use of fertilizers, pesticides, and insecticides. Consequently, concentrations of potentially toxic elements (PTE) in the soil have increased. To ...
    Geologija, Geotehničko inženjerstvo, Inženjerska geologija

  • 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 ...
    pyrazoloquinolinones, nanocrystals, wet media milling, fasted/fed bioavailability
    ... Pharmaceutics 2021, 13, 1188 3 of 19 2. Materials and Methods 2.1. Materials DK-I-60-3 was synthesized at the Department of Chemistry and Biochemistry, Uni- versity of Wisconsin—Milwaukee, WI, USA, according to the procedure explained by Knutson et al. [12]. Other materials used in this research are listed: ...
    ... approach. Generally, poorly soluble substances can be characterized as brick dust or grease balls depending on the limiting factor for the solubility: solid-state or solvation process [3,5]. Brick dust substances are poorly soluble in an aqueous environment as well as in lipids and organic solvents, and ...
    ... samples were then centrifuged for 20 min at 3400× g, and supernatants were separated. The DK-I-60-3 was extracted from plasma and supernatants by solid-phase extraction using Oasis HLB cartridges (Waters Corporation, Milford, MA, USA). The cartridges were pre- Pharmaceutics 2021, 13, 1188 6 of 19 ...

  • Upravljanje proizvodnjom nafte – novi alat na bazi fazi logike

    Мирослав Црногорац, Душан Даниловић, Лола Томић (2020)
    ... local and global companies operating in the markets of Southeast Europe. Kemis treats waste as a valuable secondary raw material, ensures that useful metallic and non-metallic materials are returned to production, while residues are prepared to be converted into energy. Keywords: management, waste ...
    ... reliable and tested materials. Knowledge of the quality of materials and their characteristics that are available during product development, as well as monitoring trends in the development of new materials are necessary elements in engineering practice. Data on available materials and their characteristics ...
    ... CAMS Abstract: The choice of materials in the engineering process of product development is a complex task. In the process of designing a machine product, the choice of materials is subject to changes in order to optimize the product. Wrong choice of materials in the initial stages of product ...

  • Tectonic evolution of the Vršac Mts. (NE Serbia): Inferences from field kinematic and microstructural investigations

    Uroš Stojadinović, Nemanja Krstekanić, Bojan Kostić, Marija Ružić, Aleksa Luković (2021)
    The Vršac Mts. in NE Serbia represent the key area to investigate structural relations between the Northern Serbo-Macedonian Subunit and Supragetic Unit of the Dacia Mega-Unit. The geodynamic events during the Variscan orogeny in the Late Paleozoic colligated the two units and led to their metamorphic differentiation. The Late Cretaceous extension exhumed the medium-grade Serbo-Macedonian metamorphic rocks and structurally juxtaposed them against the low-grade metamorphosed basement of the Supragetic Unit along an E-dipping shear zone, which outcrops in the ...
    severna srpsko-makedonska subjedinica, supragetikum, kinematska analiza, multifazna ekstenzionalna deformacija
    ... significance of Gosau-type basins for the late cretaceous tectonic history of the Alpine-Carpathian belt. Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy 24, 687–695. https://doi. org/10.1016/S1464-1895(99)00100-3 Willingshofer E., Andriessen P., Cloetingh S. & Neubauer F. 2001: Detrital ...
    ... between them (Fig. 5, Table 1). Each thin-section was cut parallel to the stretching lineation in the sample. We used optical microscopy to determine mineral assemblages, metamorphic grade, and micro-scale deforma- tions in the Serbo-Macedonian, Supragetic and their contact. The microstructures were analysed ...
    ... muscovite shows intense folding and transposition of older foliation observed by rarely preserved isoclinal fold hinges (Fig. 5b). Based on the observed mineral assemblage and recrystallization features of the main rock-forming minerals, we estimate that the primary metamorphic event that affected the Northern ...

  • Punctuated, episodic magmatism and mineralization of the Rogozna skarn-hosted Au-Zn-Pb-Cu deposits revealed through high-precision U-Pb zircon geochronology

    Sean P. Gaynor, Milorad D. Antić, Vladica Cvetković, Kristina Šarić, Urs Schaltegger (2023)
    The subvolcanic regions of magmatic centers are commonly associated with alteration, mineralization, and economic ore deposits, however the duration and frequency of mineralizing pulses within the overall lifespan of these centers can be poorly defined. Therefore, models for the formation of mineral systems require more highprecision geochronology data to refine their evolutionary models. Rogozna Mountain and its eponymous magmatic complex, located in SW Serbia, hosts multiple base metal deposits associated with variable rock types and structural expressions and serves as a natural laboratory to ...
    Skarnovska mineralizacija, Magmatsko-hidrothermalni sistemi, Subvulcanske intruzije, geohronologija na cirkonima, CA-ID-TIMS

  • Indeksi kontrole održavanja i korišćenja rotornog bagera

    Jovana Mitrović, Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Filip Miletić (2023)
    Razvoj površinske eksploatacije se u velikom stepenu zasniva na svestranoj mehanizaciji rudarskih radova. Kako bi se zadovoljili potrebni kapaciteti, neophodna je primena savremene mehanizacije, velikih kapaciteta i pouzdanosti u radu. Naime, sa stepenom povećanja mehanizovanosti radova smanjuje se broj zaposlenih radnika, povećava produktivnost rada, smanjuju troškovi po jedinici proizvoda, a samim tim i povećava ekonomičnost površinske eksploatacije. Predmet istraživanja su rotorni bageri SRs 1200 koji predstavljaju samohodne mašine kontinuiranog dejstva namenjene za otkopavanje jalovine i korisne supstance na površinskim ...
    rudarstvo, rotorni bager, indeksi održavanja, indeksi korišćenja, TOPSIS

  • Osnovi hidrogeologije

    Petar Dokmanović (2021)
    hidrogeologija, atmosferska voda, površinske vode, podzemne vode, vodni bilans, poroznost stena
    ... (specifične) gustine minerala od kojih je stena sačinjena (tabele 6.7.1.1. i 6.7.1.2). Tabela 6.7.1.1. Gustine čvrstih čestica pojedinih minerala [26-adaptirano] Mineral ρs(g/cm3) Mineral ρs(g/cm3) Kvarc 2,65 Amfibol 2,8–3,6 Feldspati 2,45–2,76 Olivin 3,3–3,4 Minerali glina 2,6–2,8 Kalcit 2 ...
    ... Živanović, 2014): rastvaranje minerala, taloženje, kompleksacija, redoks reakcije, sorpcija i jonska izmena. Voda je jedan od najboljih rastvarača u prirodi. Pod hemijskim rastvaranjem minerala podrazumeva se prevođenje mineralne materije, u vidu jona, u vodeni rastvor. Minerali su jonska jedinjenja, čije ...
    ... nti u vidu : prostih jona, molekula, koloidnih i lebdećih čestica, kao i u vidu minerala i organskih kompleksa. Izvori mikrokomponenti u PV najčešće su rudni minerali (Zn, Cu, Pb, Ag, Mo, U, As), akcesorni minerali (Be, Se), organske materije (J, Mo), morska voda (J), kao i magmatske, metamorfne ...

  • An Approach to Management Decision Support: The Coal Mine Pljevlja Management Information System

    Božo Kolonja, Ranka Stanković, Filip Vuković, Ivan Obradović (2006)
    In this paper we describe the approach that has been used in the development of the Management Information System (MIS) in the Coal Mine Pljevlja in Montenegro. The methodology of this approach was based on new information technologies and management techniques which have already been successfully applied in other related fields. Its main goal was to introduce modern management techniques to mining, adapted to specific features of the mining industry, its operations and environment, thus enabling the tactical management ...
    ... orders, which includes technical elaboration of: equipment maintenance operations, troubleshooting, required workforce per norm, all spare parts, materials and drawings necessary to carry out the works, as shown in Figure 4. Figure 3. Recording of production data This program system is used for ...
    ... for issuing and monitoring of realization of internal orders for procurement of necessary equipment or spare parts, requisitions of materials and spare parts from the warehouse, orders to the Commercial Department concerning services of third parties, orders for obtaining drawings of technical ...