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330 items

  • Петролошке карактеристике тријаских карбоната у околини Толића (Мионица)

    Михаило Вујашевић (2024)
    У тријаским теренима у околини Толића код Мионице извршено је узорковање карбонатних стена које су предмет овог рада. На одабраним узорцима утврђене су петролошке карактеристике. Главни задатак овог завршног рада представља испитивање минералошких и петрографских карактеристика карбонатних стена, применом оптичке анализе, рендгенске дифракције и калциметрије. Макроскопском детерминацијом и применом Данхамове класификације испитивани узорци су сврстани у кречњаке калкаренитског до калклутитског склопа, односно mudstone, packestone и grainstone типа. Микроскопским прегледом кречњака и применом Фолкове класификације утврђен је њихов састав и ...
    тријаски карбонати, петрографске карактеристике, класификације кречњака
    ... BpeMeHcKa KOHcTaHrTa: 10 */min Cuuka 3. PepnireHcku a(bpakroverap „Rigaku SmartLab” (Ooro C. Konau). /loOujenu monmamm 3a mnooxaje JH(O)bpaKHMOHMX MaKcCHMyMa 20(), BpeJIHOCTH MClyIUbOCHHX pacrojaba 3a cBc pedQjmekcuje, Kao H ojroBapajyhu penaTHBHH HHTeH3HTCTH ///max npakaaaHu cy rpa(buku y p ...
    ... classified as limestones of calcarenitic to calclutitic composition, specifically of the mudstone, packstone, and grainstone types. Through microscopic examination of the limestones and the application of Folk's classification, their composition was determined, and they were identified as fossiliferous ...
    ... yoxHukor. Zapisnici SGD za 1889. god., Beograd. (IIpeyaero 3 mareparype HaBeJteHe moji p. op. 15) 2. Gikić, S., 1892: Godišnjak rudarskog odeljenja min. narodne privrede, str. 176, Beograd. (IIpey3ero 3 nareparype HaBc/neHe moji p. op.15) 3. Dunham, R.J. 1962: Classification of carbonate rocks according ...

  • Improving efficiency of thermal power plants through mine coal quality planning and control

    Mirjana Banković, Dejan Stevanović, Milica Pešić, Aleksandra Tomašević, Ljiljana Kolonja (2018)
    Главни циљ контроле квалитета угља у рудницима лигнита је снабдевање термоелектрана угљем чији квалитет мора да се креће унутар одређених квалитативних ограничења. Карактеристике угља могу да утичу на ефикасност, поузданост и расположивост како котла тако и јединица за контролу емисије. У овом раду аутори су презентовали интегрисану симулацију рударског процеса као нови приступ у истраживању променљивости калоричне вредности угља приликом експлоатације комплексног лежишта лигнита. Резултати таквог приступа омогућавају драгоцен увид у перформансе континуалног рударског система у смислу контроле променљивости ...
    mine planning, variability of coal quality, simulation, coal blending
    ... ≤ Qmax (3) – Coal quality constraint. Equation (4) ensures that the coal quality does not exceed the prescribed upper and lower bound: 1 1 min max 1 ... ... n n n CV Q CV Q CV CV Q Q + + ≤ ≤ + + (4) – Optionaly, ash, eq. (5), and sulphur, eq. (6), constraints can be included as well: ...
    ... the most desirable sources escalates. Coal properties that most affect boiler operation, according to Cole and Frank [4], are ash content, ash composition, sulphur content, and moisture content. Higher ash content results in increased system throughput, increased erosion, and shortened boiler and ...
    ... and ash handling systems. Schimmoller [5] discussed coal and ash handling in search of cost savings in coal-fired handling plant. Ash composition affects and influences the slagging of furnace walls and fouling of convection passes. Fouling decreases heat transfer and promotes wastage by external co ...

  • Uniaxial compressive strength test before and after standard fire test on rock mass

    Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović (2022)
    ... paper, it is not possible to determine uniaxial compressive strength after standard fire test. Standard fire test showed that the rock is of such composition, it will disintegrate at high temperatures. For tunnel structure, this significant drop in strength after standard fire test is not dangerous ...
    ... (1) below. ( ) 2018log345 10 ++=Θ tg (1) where: t [min] time, and T [° C] temperature inside furnace depending on time t. In Figure 4 standard fire curve according to SRPS EN 1363-1 is presented. ...

  • Određivanje zbijenosti starog komunalnog otpada

    Jovana Janković, Dragoslav Rakić, Irena Basarić Ikodinović, Tina Đurić (2021)
    Bez obzira na savremene tretmane komunalnog otpada u svetu, u Srbiji je i dalje najčešći vid odlaganja na komunalne deponije, pa zbijanje otpada predstavlja jednu od ključnih faza formiranja deponije. Na ovaj način znatno se smanjuje zapremina otpada, ubrzava proces degradacije i produžava radni vek deponije. Zbog toga su geotehničke karakteristike komunalnog otpada prilikom zbijanja, veoma bitne kako u fazi projektovanja tako i u fazi izgradnje deponije i optimizacije prostora. Tu se pre svega misli na maksimalnu suvu zapreminsku ...
    komunalni otpad, deponija, Proktorov opit, optimalna vlažnost, maksimalna suva zapreminska težina

  • Testing the energy value of different types of coal by the method of active thermography

    Stevan Đenadić, Ljubiša Tomić, Vesna Damnjanović, Predrag Jovančić, Dragutin Jovković (2020)
    In this paper, coal thermograms are presented and analyzed in order to determine their energy value. Two types of coal of different categories, brown and lignite, were selected for active thermographic imaging. The tested coal samples were processed before measurement so that they are similar in dimensions and have two plane-parallel smooth surfaces. The test samples were "primarily" heated under the same conditions and the process of their cooling was monitored by a thermal camera. "Then" they were cooled ...
    Infrared imaging, nondestructive testing, active thermography, coal.
    ... monitoring the temperature change on the surfaces of the samples due to their inhomogeneous structure, which is a consequence of the different composition of coal, were also emphasized. References [1] Gaussorgues, G. Infrared Thermography. English language edition. Springer-Science, Berlin, Germany ...

  • Развој геолошког информационог система Републике Србије

    Бранислав Благојевић, Бранислав Тривић, Ненад Бањац, Ранка Станковић, Велизар Николић (2005)
    Геолошки информациони систем Србије (ГеолИСС) је пројектован, првенствено, са намером ефикасног дигиталног архивирања геолошких и њима сродних података. У овом раду је приказана структура базе података као основа за развој геолошки конципираног ГИС-а. Нови, објектно орјентисани (О-О) начин моделирања омогућио је дефинисање самосталних типова објеката, хијерархијски повезаних кроз тополошке и друге релације, чиме је обезбеђена њихова медјусобна интеракција. Објектно оријентисано моделирање извршено је коришћењем унифицираног језика моделирања (UML) и CASE алата, кроз концептуални и логички ниво. Физички модел ће ...
    ГеолИСС, геолошки подаци, управљање базама података, концептуални модел, логички модел, ГИС

  • Dehydroicetexanes in sediments and crude oils: Possible markers for Cupressoideae

    Hans Peter Nytoft, Geir Kildahl-Andersen, Sofie Lindström, Frode Rise, Achim Bechtel, Danica Mitrović, Nataša Đoković, Dragana Životić, Ksenija A. Stojanović (2019)
    Two previously unidentified dehydroabietane isomers were isolated from Miocene Serbian lignite and Rhaetian (Late Triassic) coaly mudstones from South Sweden and characterized using NMRspectroscopy as cis- and trans-dehydroicetexane. Both have a 9(10?20)-abeo-abietane or icetexane skeleton, consisting of a 6-7-6 tricyclic framework with seven carbons in ring B instead of the usual six in common diterpanes of the abietane-type. Dehydroicetexanes can be detected using GC-MS-MS in m/z 270?146 chromatograms without interference from dehydroabietane or other isomers. Dehydroicetexanes are often abundant ...
    Geochemistry and Petrology
    ... (30 m � 0.25 mm i.d., film thickness 0.10 mm) was used. The injection temperature was 70 �C (2 min hold). The temperature program was: 30 �C/min from 70 to 100 �C and 4 �C/min from 100 to 308 �C (held 8 min). Argon was used as collision gas for MS-MS experiments. For M+ daughter scans and multiple reaction ...
    ... column (30m ~x0.25mm i.d., film thickness 0.10 ym) was used. The injection temperature was 70°C (2 min hold). The temperature program was: 30°C/min from 70 to 100 °C and 4°C/min from 100 to 308 °C (held 8 min). Argon was used as collision gas for MS-MS experiments. For M* daughter scans and multiple reaction ...
    ... 0.25 mm film thickness) was used. The oven temperature gradient was programmed from 70 �C to 300 �C at 4 �C/min, followed by an isothermal period of 15 min at 300 �C. Helium (flow 1.2 cm3/min) was used as carrier gas. Commercial CO2 was injected at the beginning and end of each analysis as monitoring ...

  • Mineral Resources of Serbia: Environmental, Societal and Economic Challenges

    Vladimir Simić, Rade Jelenković, Dragana Životić (2019)

  • Polyhedral characteristics of the cosalite-type crystal structures

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus (2019)
    kristalna struktura, kozalit, poliedarske karakteristike
    ... followed by the multi-scan method (Blessing 1995) as implemented in the SCALE3 ABSPACK scaling algorithm within CrysAlis PRO. Chemical Composition Chemical composition and sample homogeneity were first determined using a JEOL JSM–6610LV scanning electron microscope (SEM) connected to an INCA energ ...
    ... Diffraction) Absorption correction Analytical No. of measured, independent, and observed [I . 2r(I)] reflections 8153, 1756, 1516 Rint 0.052 (sin h/k)max (Å –1) 0.581 Refinement R[F2 . 2r( f2)], wR( f2), S 0.031, 0.080, 1.12 No. of reflections 1756 No. of parameters 119 Dqmax, Dqmin (e Å –3) 2.14 ...
    ... 5. Structural charac- teristics for individual coordination polyhedra are given in Table 6. Variations of unit-cell parameters with chemical composition in cosalite-type structures are given in Table 7, and variations of mean polyhedral distances as a function of polyhedral distortion are presented ...

  • Development of a petrographic classification system for organic particles affected by self-heating in coal waste. (An ICCP Classification System, Self-heating Working Group – Commission III)

    M. Misz-Kennan, J. Kus, D. Flores, C. Avila, Z. Büçkün, N. Choudhury, K. Christanis, J.P. Joubert, S. Kalaitzidis, A.I. Karayigit, M. Malecha, M. Marques, P. Martizzi, J.M.K. O'Keefe, W. Pickel, G. Predeanu, S. Pusz, J. Ribeiro, S. Rodrigues, A.K. Singh, I. Suárez-Ruiz, I. Sýkorová, N.J. Wagner, D. Životić (2020)
    Self-heating of coal waste is a major problem in the leading coal-producing and consuming countries, independent of the recent or past coal exploitation history. The phenomenon of self-heating is dependent on many factors such as the properties of organic matter (maceral composition and rank), moisture and pyrite content, climate effects, and storage conditions (shape of the dump or compaction of the coal waste). Once deposited, coal waste undergoes oxidation, which can lead to self- heating with the overall temperatures ...
    Stratigraphy,Economic Geology,Geology,Fuel Technology
    ... morphological forms of organic matter in coal wastes by participants of 2015 and/or 2016 Round Robin Exercises. Type of particle 2015 2016 Min Max Aver Min Max Aver Organic particle 93.3 100.0 98.4 96.7 100.0 98.6 Mineral particle 99.1 100.0 99.6 96.7 100.0 99.4 Non-altered 60.0 100.0 93.3 63.3 100 ...
    ... or past coal exploitation history. The phenomenon of self-heating is dependent on many factors such as the properties of organic matter (maceral composition and rank), moisture and pyrite content, climate effects, and storage conditions (shape of the dump or compaction of the coal waste). Once deposited ...
    ... waste presented in this paper is based on several years of research of the Self-heating of Coal and Coal Waste Working Group. 1.1. The origin and composition of coal waste Coal wastes in the coal mining industry are divided into two main groups according to their origin: (1) mining wastes associated with ...

  • Пројекат ПРИЗМА: Карактеризација и технолошки поступци за рециклажу и поновну употребу флотацијске јаловине рудника „Рудник“

    Владимир Симић, Стефан Петровић, Филип Арнаут, Весна Цветков, Милена Костовић, Драган Радуловић, Јовица Стојановић, Владимир Јовановић, Дејан Тодоровић, Нина Николић, Јелена Сенћански, Грозданка Богдановић, Драгана Мариловић (2024)
    Prizma, REASONING, Rudnik, jalovina, Fond za nauku Republike Srbije

  • Influence of DEM resolution on numerical modelling of debris flows in RAMMS - Selanac case study

    Jelka Krušić, Biljana Abolmasov, Mileva Samardžić Petrović (2019)
    Debris flows induced by intensive rainfall represent very hazardous phenomena in many parts of the World. Methods for prediction of runout distance of flow like mass movements are different and depending on the input data, rheology, and available or appropriate numerical solution. However, sometimes it is not easy to obtain pre event and post event high-resolution data in the rural or mountainous area. Thus, the topology of terrain is the most important input parameter for the every real case ...
    tecišta, modeliranje, RAMMS, DEM

  • Demise of the Wetterstein Carbonate Platform and onset of the Dachstein Carbonate Platform recorded in deep-water successions of the East Bosnian-Durmitor megaunit (Pliješevina, northern Montenegro, Dinarides)

    Milica Mrdak, Eva Wagerer, Milan Sudar, Nevenka Djerić, Martin Đaković, Hans-Jürgen Gawlick (2024)
    Triassic, Carnica event, clay mineralogy, conodont biostratigraphy, Neo-Tethys

  • Method validation and geochemical modelling of chromium speciation in natural waters

    Piotr Rusiniak, Katarzyna Wątor, Ewa Kmiecik, Vesna Ristić Vakanjac (2024)
    The study focuses on validating reference methods such as ICP-OES and ICP-MS for detecting ultratrace levels of chromium in groundwater, where concentrations are typically very low. Additionally, it verifies a hyphenated technique, IC-ICP-MS, for determining naturally occurring Cr(VI) in tested waters. The validation process involved various chromium analysis variants, including isotopes 52Cr and 53Cr in ICP-MS and IC-ICP-MS techniques, along with specific emission lines in the ICPOES technique. Statistical data processing revealed that the achieved limits of quantification for ...
    шестовалентни хром, ИЦ-ИЦП-МС, технике са цртицама, геохемијско моделирање, анализа спецификација, валидација методе

  • Sastav i teksture minerala FeO-Fe2O3-TiO2 sistema u vulkanskim stenama i porfirskim ležištima bakra Borske metalogenetske zone

    Aleksandar Luković (2021)
    Proces obrazovanja minerala iz sistema FeO-Fe2O3-TiO2 u uzorcima vulkanskih stena i porfirskih orudnjenja borske zone prikazan kroz pojavu magnetita/hematita i njihovih alteracija. Minerali ove zone su ispitivani optičkim metodama (odbijena i propuštena svetlost), SEM-EDS/BSD, XRPD, LA-ICP-MS metodama. Rezultati ispitivanja su, pored glavnih Fe – Ti oksida, otkrili prisustvo ferijskog ilmenita u hornblenda andezitima I vulkanske faze kao i magnetita sa većim koncetracija Cr u zoni zlotske magnetne anomalije. Ispitivanje uzoraka iz bušotina porfirskih sistema borske zone otkriva postojanje nekoliko ...
    magnetit, hematit, hemoilmenit, Borska metalogenetska zona, porfirska ležišta

  • Kvartarni klastiti iz bušotine kod Aranđelovca (rasadnik Mladost)

    Miroslav Radeta (2024)
    U ovom radu analizirani su kvartarni klastiti iz bušotine kod Aranđelovca IB 18-3, sa ciljem boljeg razumevanja njihovih sedimentoloških i litoloških karakteristika. Kvartarni sedimenti su prilično homogenog/uniformisanog sastava i čine ih finozrni klastiti (dominantno alevroliti) sa određenim procentom peskovite i glinovite frakcije. Oni su iskartirani u samoj povlati i debljina im je 27 m. U podini su gornjokredne karbonatne stene (krečnjaci, laporci, rekristalisali/mermerisani karbonati) i miocenski sediment predstavljeni raznovrsnim varijetetima klastično karbonatnih stena. Ispitivani kvartarni sedimenti odlikuju se odsustvom ...
    kvartarni klastiti, alevriti, Aranđelovac, granulometrija, mineraloško petrografski sastav
    ... alming to better understand their sedimentological and lithological characteristics. The Quaternary sediments are fairly homogeneous/uniform in composition, primarily consisting. of fine-grained clastites (dominantly siltstones) with a certain percentage of sandy and clay fractions. These sediments ...
    ... themselves are of deluvial-proluvial origin. Key words: Quaternary clasts, siltstones, 4randjelovac, granulometry, mineralogical petrographic composition SADRŽAJ J UPOD....aeeaeee e aeeaaeaaeaeaeeaeeaeeeeeeeaeeeeeeaeeeeeeeeeveeeeeeeeeeeeeee 1 PA IJ XOR RRRRIGRRARRRIGIARRRIGIOIRRRRGGOGIGGRROIG ...

  • Numerical modeling of Selanac debris flow propagation using SPH code

    Jelka Krušić, Biljana Abolmasov, Miloš Marjanović, Manuel Pastor, Saeid M. Tayyebi (2021)
    The Selanac debris flow is a very huge event triggered after extreme rainfall caused by Cyclone Tamara activity in the Republic of Serbia in May 2014. The Selanac case study was already modelling in different programs using Voellmy rheology assumptions like RAMMS software. In this paper research are focusing particularly on the process of debris flowing from initiation zone to main deposition area using Geoflow SPH two-phase model considering frictional rheology law. Main rheological parameters are back-calculated using also ...
    debris flow, modelling, SPH code, DEM

  • Hydrogeochemistry of Uranium in the Groundwaters of Serbia

    Marina Ćuk, Maja Todorović, Petar Papić, Jovan Kovačević, Zoran Nikić (2015)
    ... Groundwaters of Serbia 3 Table 1. Statistical summary of major hydrochemical parameters and uranium concentrations in groundwater samples. Min Median Max Mean T (ºC) 8 21.55 77.9 26.99 EC (µS/cm) 95 1408 28925 2189.29 pH 5.75 7.28 9.72 7.32 EMS (V) –0.226 0.1865 0.4265 0.15 Ca (mg/L) 0 ...
    ... different chemical parameters in- cluding uranium. For each groundwater sample, information was compiled about the basic parameters of its chemical composition. Most of the samples were found to be of the Na – HCO3 and Ca, Mg − HCO3 water types, while only a few were classified as the Ca, Mg – SO4 or ...
    ... tectonomagmatic events controlled by the early extensional phases in the opening of the Pannonian Basin (Cvetković et al. 2007). Endogenic uranium min- erals are spatially and genetically associated with granitic rocks of Bukulja Mt. Uranium minerals can also be found deposited in clastic sediments ...

  • Integrated Stratigraphy of the Middle–Upper Jurassic of the Krížna Nappe, Tatra Mountains

    Renata Jach, Nevenka Đerić, Špela Goričan, Daniela Reháková (2014)
    carbon and oxygen isotopes, radiolarians, calcareous dinoflagellates, radiolarites, Krížna Nappe, West ern Carpathians, Tethys
    ... isotope composition of Oxfordian-Early Kimmeridgian belemnite rostra: palaeo- environmental implications for Late Jurassic seas. Palaeoge- ography, Palaeoclimatology, Palaeoecology, 203: 153—168. Wierzbowski, H., Dembicz, K. & Praszkier, T., 2000. Oxygen and carbon isotope composition of Cal ...
    ... an age. These facies pass into Upper Kimmeridgian-Lower Tithonian pelagic carbonates with abundant Saccocoma sp. The bulk-carbonate isotope composition of the carbonate-siliceous deposits shows positive and negative &5C excursions and shifts in the Early Bajocian, Late Bajocian, Early Bathonian ...
    ... dusky red, pinkish and greyish pink. The 45 bulk samples from the upper 60 m ofthe Filipka Valley section were analysed for stable isotope composition (Fig. 7). The ŠIŠC curve shows a slightly scattered pattern that probably results from the lower sampling resolution. In the uppermost part ...

  • Mesozoic carbonate rocks in Serbia used as dimension stone

    Vesna Matović, Tijana Vojnović Ćalić (2016)
    The building industry in Serbia uses, to a great extent, imported natural stone for architectural purposes. The significance of local deposits, particularly limestones, is not adequately perceived despite the country’s abundance of these valuable resources. Therefore, this study focuses on Serbia’s Mesozoic carbonate rocks, specifically on the deposits of four selected quarries: Klisura, Skrzut, Struganik, and Tisnica. The quality and prospects of the application of these limestones has not yet been the subject of a detailed, comprehensive investigation. Therefore, ...
    Ukrasni kamen, Mezozoik, Krečnjak, Srbija, Petrografija, Fizičko-mehanička svojstva
    ... Leica DMLSP microscope for polarized light connected to a Leica DC 300 digital camera. The thin sections were used to determine the mineral composition and microtextural features (size and type of allochem) for the purpose of rock classification, according to Folk (1959) and Flugel (2004). ...
    ... slightly and is in range of 2,650–2,690 kg/ m* (Fig. 4a). The values of real density (2,700–2,712 kg/ m?) are in accordance with the mineral composition of these almost pure limestones (the main mineral is calcite with a density value of 2,710 kg/m?*; Fig. 4a). The constant real density values ...