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Упит dcterms_subject_txt:rock mass

264 items

  • Structural characterization of traditional pottery produced from local clay, Rujište (Ražanj, Central Serbia), in an effort to preserve its geoheritage

    Maja Milošević, Biljana Đorđević, Alena Zdravković (2021)
    ... group of feldspar, which are firmly bound in the basic mass. In most cases, coatings of iron oxide are observed on the grains of minerals. There is a uniformity in the ratio of coarse-grained particles and the fine-grained fraction in the basic mass. Microcrystalline clasts could not be accurately identified ...
    ... with a very smaller amount of detrital quartz and feldspar (Krstić et al., 1980). In the analysis of the thin sections made of the sample, the basic mass is observed, which represents a sintered fine-grained aggregate and binds large, often idiomorphic clay aggregates. Observation under the crossed ...

  • Primena programa UVSZ pri zaštiti od miniranja

    Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac, Rade Tokalić (2021)
    Primena energije eksploziva tj. miniranje, predstavlja osnovni način eksploatacije čvrstih mineralnih sirovina u rudarstvu. Miniranjem se postižu vrlo povoljni tehnoekonomski pokazatelji, koje nažalost prate i negativni efekti miniranja. U cilju zaštite životne sredine potrebno je za svaku radnu sredinu odrediti jednačinu oscilovanja stenske mase pri miniranju. Ova jednačina definiše promenu brzine oscilovanja stenske mase u zavisnosti od rastojanja, količine eksploziva, uslova izvođenja miniranja i geoloških karakteristika stenske
    Program UVSZ, miniranje, potres, zaštita životne sredine
    ... determine the rock mass oscillation equation for each working environment during blasting. This equation defines the change of rock mass oscillation velocity depending on distance, explosive amount, conditions of blasting and geological characteristics of rock mass. Oscillations of the particles of rock mass ...
    ... necessary to determine the rock mass oscillation equation for each working environment during blasting. This equation defines the change of rock mass oscillation velocity depending on distance, explosive amount, conditions of blasting and geological characteristics of rock mass. Oscillations of the particles ...
    ... particles of rock mass at terrain are felt as shock. Based on application of this equation, we are able to predict the oscillation velocity for each subsequent blasting in a given working environment. On that way, shocks from blasting, in a seismic sense, are brought under control. In this paper ...

  • Application of stochastic models for mine planning and coal quality control

    Dejan Stevanović, Božo Kolonja, Ranka Stanković, Dinko Knežević, Mirjana Banković (2014)
    ... algorithm developed considers the number of layers in piles and the contribution that each seam from each block adds to the total mass of the pile. When the number of layers and mass (size) of the pile is reached the algorithm stops, takes the weighted average of the qualities from the blocks included in ...
    ... In this context, the most important factors, in respect to pile building can be cited as the type of layer disposition, number of layers and added mass. The last variable can signifi- cantly reduce pile variability when a large material amount is homogenized, and variability among the lots decreases ...
    ... depends on the equipment used and the way coal is stocked and reclaimed [6]. The main factors influencing blending efficiency are the pile size or its mass and the number of layers used to build pile. The aim in the homogenization process is to narrow down the standard deviation of the normal distribution ...

  • The use of biological markers in determination of origin and type of organic matter in the Tisza river sediments

    Snežana Štrbac, Gordana Gajica, Aleksandra Šajnović, Nebojša Vasić, Ksenija Stojanović, Branimir Jovančićević (2013)
    The objective of the study was to determine the origin and type of organic matter (OM) of the Tisza recent sediments along the distance of 153 km through the territory of Serbia. For this purpose group organic-geochemical parameters and biomarker compositions were used. All samples contain approximately same amount of OM, which was deposited under uniform, slightly reducing conditions. Based on the distribution of n-alkanes, the origin and type of OM could not be precisely estimated. However, n-alkane patterns ...
    sediments, Tisza River, organic matter, biomarkers, oil pollutants
    ... The saturated hydrocarbons were analyzed by gas chromatography–mass spectrometry (GC–MS). A gas chromatograph Agilent 7890A GC (H5-MS capillary column, 30 m×0.25 mm, He carrier gas 1.5 cm3 min-1, FID) coupled to an Agilent 5975C mass selective detector (70 eV) was used. The column was heated from ...
    ... determined for the full distribution of n-alkanes C16–C35 (mass chromatogram m/z 71), CPI (C16–C35) = 1/2 [Σodd(n-C17–n-C35) / Σeven(n-C16–n-C34) + Σodd(n-C17–n-C35) / Σeven(n-C18–n- –C36)]; bCPI determined for the distribution of n-alkanes C16–C22 (mass chromatogram m/z 71), CPI (C16– –C22) = 1/2 [Σodd( ...
    ... ), m/z = 191 (terpanes) and m/z = 217 (steranes). The individual peaks were identified by comparison with literature data12 and based on the total mass spectra (library: NIST5a). The biomarker parameters were calculated from the GC–MS chromato- gram peak areas (software GCMS Data Analysis). RESULTS ...

  • 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 материјалима

  • Age and microfacies of oceanic Upper Triassic radiolarite components from the Middle Jurassic ophiolitic mélange in the Zlatibor Mountains (Inner Dinarides, Serbia) and their provenance

    Hans-Juergen Gawlick, Nevenka Đerić, Sigrid Missoni, Nikita Bragin, Milan Sudar, Divna Jovanović (2017)
    Neo-Tethys, trench-like basins, synorogenic deposition, evolving thrust belt, Triassic palaeogeography
    ... advancing nappes. These deep-water basins were supplied by the erosional pro- ducts of the advancing nappe stack. Several types of mass transport deposits (for a review on Mass Transport Deposits see: Shanmugam 2015) are incorporated in such a turbiditic radiolaritic-argillaceous matrix. Later, these ...
    ... DINARIDES 351 often masked by the younger and polyphase tectonic motions (Schmid et al. 2008). In addition, synorogenic sedimentary basin fills or mass transport deposits in trench-like basins in front of a propagating nappe stack, are commonly overprinted by multiple deformational events or reworked ...
    ... B) a sedimentary mćlange formed in front of the obducted ophiolites in trenches or foredeeps, or C) an original sedimen- tary olistostrome and mass transport dominated deep-water basin fill in front of an advancing nappe stack later incorpo- rated in the nappe stack forming an olistostromal ...

  • Flyrock induced by blasting in surface mining

    Milanka Negovanović, Lazar Kričak, Snežana Ignjatović, Stefan Milanović, Jovan Marković, Nikola Simić, Rade Šarac (2022)
    Miniranje predstavlja i dalje najefikasniji i najjeftiniji način eksploatacije velikih količina čvrstih mineralnih sirovina na površinskim kopovima. Energija eksplozije se koristi za fragmentaciju čvrste stenske mase do zahtevane granulacije. Pored pozitivnih efekata miniranja, postoje i određeni neželjeni efekti svakog procesa miniranja koji se mogu javiti, a to su: potresi tla, razletanje komada stene, vazdušni udari, otrovni i zagušljivi gasovi i prašina. Razletanje komada stene je nekontrolisano izbacivanje fragmenata odminirane stenske mase i predstavlja jedan od glavnih izvora materijalne štete ...
    razletanje, bušenje, miniranje, površinska eksploatacija, bezbednost, nesreća

  • Merenje mase iskopanog uglja na površinskim kopovima

    Snežana Aleksandrović (2015)

  • Debris-flow Susceptibility Assessment in Flow-R: Ribnica River Case Study

    Ksenija Micić, Miloš Marjanović, Biljana Abolmasov (2024)
    Debris flows are among the most dangerous erosional geohazards due to the fast rate of movement and long runout zones. Even though the initiation can be triggered in mountainous areas, inhabited and with steep slopes, their propagation and deposition can endanger not only buildings and infrastructure in the urbanized areas, but also threaten human lives. As these initiation areas usually represent unattainable terrains with rapid vegetation cover development, field observations and aerial photo analysis become high-demanding tasks. Consequently, medium-to-regional ...
    tečenje drobine, Flow-R, procena podložnosti, empirijski model

  • Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic

    Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković (2020)
    Artificial lift methods have applications in oil wells where oil production is no longer possible due to natural reservoir energy, so this necessary energy is added by introducing lift methods. In order to achieve optimum production, the selection of an artificial lift method is very important. This paper uses fuzzy logic as a mathematical and conceptual model for selection of the optimal artificial lift method. The outcome or IF-THEN rules, as the central part of the model, is based ...
    mehaničke metode, proizvodnja nafte, fazi logika, donošenje odluka, optimizacija
    ... are displayed in a coordinate system that involves the center of mass (weighted mean of maximum) and the mathematical deviation (Figure 7). Energies 2020, 13, 1758 12 of 15 Energies 2020, 13, x 13 of 15 Figure 7. Center of mass and standard deviation outputs for a new well in relation to the ...
    ... considerable number of parameters being at the limit values (1 or 10). Figure 7. Center of mass and standard deviation outputs for a new well in relation to the standards for the other methods. Center of mass By calculating the weighted mean of maximum, defuzzification is done and the value of the ...
    ... The center of mass and standard deviation are calculated for each of the model results. The standards of artificial lift methods were obtained by summing together many wells with good results from applying the appropriate method. For each summed surface, we calculated the center of mass and standard ...

  • Mineralogical study of clays from Dobrodo, Serbia, for use in ceramics

    Maja Milošević, Predrag Dabić, Sabina Kovač, Lazar Kaluđerović, Mihovil Logar (2019)
    keramika, glina, Dobrodo, mineralogija, sirovina, Srbija

  • Coal homogenization stockyard sizing “Tamnava – Zapad” case study

    Božo Kolonja, Dinko Knežević, Ranka Stanković, Dejan Stevanović, Detlef Trummer (2016)
    ... Coal mass, total 400,000 t 375,000 t Coal mass per package 100,000 t 65,000 t Reserve 8 days 7.5 days Time per package 6 shifts 4 shifts Max. number of filled packages 2.5 4.5 Min. number of filled packages 1.5 1.5 Max. coal mass at coal yard 250,000 t 270,000 t Min coal mass at coal ...
    ... sizes to be equal, the stacker has to change travel speed depending on the quantity of coal arriving at the stockyard. The regulation unit applied is mass per minute. Thus the stacking speed for the selected method depends on the number of layers, the stacking capacity and the constructional capabilities ...

  • Failure Estimation of the Majdanpek Open Pit East Face Based on Inverse Velocity Model

    Miloš Marjanović, Stefan Milanović, Nikola Simić, Lazar Kričak (2024)
    The Majdanpek open pit mine south district is currently active mining prospect of copper ore exploitation in eastern Serbia. Its depth is approaching the termination depth and occurrences of large-scale instabilities and global instability of the final pit slope is possible. These can generate catastrophic mass movement inside an area that encloses a regional road route and the Pek River bed which is channelled along the outer contour of the pit. The displacements that were noted in early 2023, in the ...
    displacement, survey, inverse velocity, open pit

  • Maturation and isotopic changes of individual hydrocarbons in lignite lithotypes through diagenesis and early catagenesis

    Ivan Kojić, Achim Bechtel, Reinhard Sachsenhofer, Dragana Životić, Ksenija Stojanović (2019)
    ... analysis which inđicate that the first significant mass 1055 (after releasing ог moisture) occurs between 400 "С and 500 %C. Aliphatic апд aromatic fractions isolated from lignite extracts and hquid pyrolysis prođucts were analyzed by gas chromatography-mass spectrometry. Carbon isotope determinations (65С) ...

  • 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
    ... and in comparison, to BaTiOyx /NiFe>»Ou and BaTiOa / ZnFe>»Ox, mass magnetization enhancement can be explained by the most significant grain size incre- ment as the sintering, temperature increased, Figure 4 and Table 2. The change in mass magnetization value in the temperature range from 20 ?C to ...
    ... Fe)pOa sin- tered at 1150 ?"C, there was a sharp fall in mass magnetization due to the phase transition caused by partial destruction of the domain structure within the crystallites from 340 *C to 400 ?C, followed by a gentle fall in mass magnetization up to 480 ?C. Then, the biggest fall due to ...
    ... BaTiOys /NiFe>»Ou, BaTiOys /ZnFe>Ou, and BaTiOy / Nip s Zno ,s Fe)Oa samples (Ba-cyan; Zn-yellow; Ni-orange; Fe-magjenta; Ti-blue; O-green). Table 2. Mass magnetization values of sintered samples at room temperature. Sample M [emu/g] BaTiOys //NiFe>»Ou 1150 *C 12.46 BaTiOa/ZnFe>Oa 1150 ?C 1.74 BaTiOy ...

  • Димензионисање транспортера на спољашњем одлагалишту повшинског копа Западни Костолац

    Петар Миловановић (2024)
    У савременом рударству, површински копови угља наилазе на различите проблеме које треба превазићи зарад добијања потребне количине угља. Као највећи потрошачи овог енергента су термоелектране, на основу овога можемо да закључимо колико су блиско повезани добра и континуирана производња на површинском копу и рад термоелектрана. Са задатком да се обезбеди стабилна и континуирана производња, потребно је да се направи добар одабир транспортера. У овом раду, за димензионисање потребног транспортера са траком, коришћен је програмски пакет Helix.Програмски пакет Helix представља један ...
    транспортна трака, снага погона, затезна чврстоћа, угаљ, Западни Костолац, Helix
    ... Density 0.369 m2 Belt and Material Mass Belt Actual % Full at High BD 83.8 % Belt Top Cover Mass 35.8 ko/m Flooded Belt Capacity at 1700kgim3 Belt Bottom Cover Mass 17.9 kg/m Flooded Belt Load Area at Zero Belt Carcass Mass 21.4 kg/m Edge Distance 0.5941 m2 Belt Mass Wb (per linear m) 82.5 ko/m Flooded ...
    ... Flooded Belt Capacity 16821 tonnes/hr Material Mass Wm 627.2 kg/m Flooded Belt Material Mass 1004.8 kg/m Total Mass (Wb + Wm) 709.7 kg/m Total Belt Mass (Wb x L) 297380 kg Designers Comments {eif\anahdefiO\aftang1033(Voribi(VOViswias MS Sans Serit:} \Viewkind4\uc1\pard\0\fs16 \par} EaciavaiZav ...
    ... Run Safety Factor ST 2000 7.95 Top Cover Thickness 16 mm Belt Rated Tension 300 kN/m Bottom Cover Thickness 8 mm Belt Total Length 3604.6 m Belt Mass 82.50 kg/m Belt Tensions and Power Calculations . ISO Effective Tens. Fully Loaded 381.97 kN Belt Power - Empty Belt 311.67 kW Maximum Tension ...

  • Dynamic and Static Elastic Properties - Laboratory Investigations of Metamorphites of the "Vranjska Banja" Series

    Jelena Majstorović, Bojan Dimitrijević, Suzana Lutovac, Snežana Savković, Miloš Gligorić (2021)
    Metamorphites of the series “Vranjska banja” built predominantly of high crystallinity schist series, alternately layered double mica, gneiss, leptonite and micaschist. For the construction of the “Prvonek” dam were carried out laboratory investigations of dynamic and static elastic properties on micashist and gneiss samples in the perpendicular and parallel direction to the foliation. These investigations provided monitoring of the rock mass anisotropy properties and greater reliability of the design parameteres. As the design of mining and construction facilities becomes ...
    micashist, gneiss, foliation, dynamic properties, static properties

  • Верификација етажних транспортера на угљеном систему – површински коп Дрмно

    Тамара Андрејевић (2024)
    У савременом рударству, површински копови угља наилазе на различите проблеме које треба превазићи зарад добијања потребне количине угља. Као највећи потрошачи овог енергента јављају се термоелектране, где на основу овога можемо да закључимо колико су блиско повезани добра и континуирана производња на површинском копу и рад термоелектрана. Са циљем да се обезбеди стабилна и континуирана производња, потребно је да се направи добар одабир транспортера. У овом раду, за потребе верификације затезне чврстоће траке и снаге погона транспортера, коришћен је ...
    транспортна трака, снага погона, затезна чврстоћа, угаљ, Дрмно, Helix
    ... 0.1987. m2 Belt and Material Mass Belt Actual % Full at High BD 53.3 % Belt Top Cover Mass 35.8 kg/m Flooded Belt Capacity at 960kg/m3 Belt Bottom Cover Mass 17.9 kg/m Flooded Belt Load Area at Zero Belt Carcass Mass 19.3. kg/m Edge Distance 0.4942 m2 Belt Mass Wb (per linear m) 82 kg/m Flooded ...
    ... Flooded Belt Capacity 8881 tonnes/hr Material Mass Wm 190.7 kg/m Flooded Belt Material Mass 474.4 kg/m Total Mass (Wb + Wm) 272.7 kg/m Total Belt Mass (Wb x L) 266443 kg Designers Comments {\rtfi\ansi\deff0\deflang1033{\fonttbn{\f0\fswiss MS Sans Serif;}} \viewkind4\uc1\pard\f0\fs16 \par} E ...
    ... Strength % Used (Running) ıi. I —s o 10 20 3a 4 e -j 7 LJ Bel Tensions & Takeup Mass Bffective Tension 21753 kN Ficton Adjustment Factor: Maximum Tension (Run) 37096 kN 1 Minimum Tension (Run) 14220 kN Takeup Mass 32270 kg Calculated & installed Power instaled Power 2,520.00 kW. Absorbed ...

  • Application of softwares for drilling and blasting

    Stefan Milanović, Lazar Kričak, Milanka Negovanović, Nikola Simić, Jovan Marković (2019)
    U današnje vreme softveri se sve više primenjuju u rudarstvu kroz eksploataciju mineralnih sirovina, projektovanje rudnika, u obavljanju različitih operacija na terenu i sl. Među softverima za rudarstvo, postoje softveri za specifične rudarske operacije, kao što su operacije bušenja i miniranja. Ovi procesi su veoma važni u eksploataciji čvrstih mineralnih sirovina, jer predstavljaju najjeftiniji i najefikasniji oblik fragmentacije stenske mase. Kroz rad, predstavljeni su neki od softvera u kombinaciji sa modernim tehnologijama, koje se koriste širom sveta i koje ...
    softver, moderne tehnologije, miniranje, bušenje, minsko polje

  • Pećina Peštera kod Laznice - primer razvića speleoloških objekata u zoni raseda (rasednoj breči)

    Mihajlo Mandić, Ana Mladenović (2022)
    Pećina Peštera se nalazi istočno od sela Laznica kod Žagubice. Iako lako pristupačna za posetioce i istraživače, do sada nije bila predmet detaljnijih istraživanja. Pominje se samo u prikazu arheološki interesantnih objekata okoline Žagubice, ali sa svedenim i uglavnom netačnim podacima o morfološkim karakteristikama. Speleološki značaj joj daje, pored relativno velikih dimenzija dvorane, njen razvoj u tektonski veoma oštećenoj zoni ukrštanja dva raseda što za posledicu ima potpunu dezintegraciju stenske mase u breču. Proces karstifikacije breče formira specifične morfološke ...
    speleomorfologija, breča, Laznica, Žagubica