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Упит dcterms_subject_txt:grain size distribution

508 items

  • Kristalografsko proučavanje strukturne desimetrizacije granata grosularsko-andraditske izomorfne serije

    Pavle I. Tančić (2016-09-21)
    U ovoj Doktorskoj disertaciji proučavano je pet različitih zona makroskopski zonarnog grandita sa lokaliteta Meka Presedla (Kopaonik, Srbija). Pomoću hemijske i elektronske analize mikroprobe preračunati su relativno visoko homogeni sastavi zona, t.j.: Grs64±1Adr36±1Sps2 (A), Grs62±1Adr38±1Sps2 (B), Grs59±2Adr40±2Sps2 (C), Grs58±2Adr41±2Sps2 (D) i Grs58±1Adr41±1Sps2 (E). Glavne promene u sastavima izražene formulom: Ca2,93-2,97Mn0,05-0,06Mg0,00-0,01Al1,14-1,26Fe3+0,72-0,83Ti0,00-0,02Si2,97-3,02O12 ukazuju da je jedina značajnija varijacija ustanovljena samo kod Al-Fe3+ raspodela u oktaedarskom položaju. Ovakav hemijski sastav je potvrđen i sa matematičkim proračunima iz IC i Raman analiza. Urađena ...
    Macroscopically zoned grandite, chemical analysis, electron microprobe analysis, Raman, Rietveld, structure, dissymmetrization, space group

  • Uticaj klimatskih promena na vodne resurse: primer sliv reke Mlave

    Vesna Ristić Vakanjac, Saša Milanović, Ljiljana Vasić, Boris Vakanjac, Saša Bakrač, Radoje Banković, Veljko Marinović (2023)
    Na teritoriji Jugositočne Evrope, pa samim tim i u delu gde živimo (Republika Srbija i Republika Bosna i Hercegovina) za očekivati je da dođe do značajnijeg porasta temperature vazduha u značajnijoj meri, što će imati značajnijeg uticaja na padavine, njihovu unutargodišnju raspodelu, kao i pojavu sve više prisutnih ekstremnih vrednosti (izuzetno sušnih i kišnih godina). Sve ovo će uticati i na sam režim površinskih i podzemnih voda, resursa bez kojih život na ovoj planeti ne bi ni postojao. Da ...

  • Depth estimation of archeological objects using Euler 3D deconvolution of magnetic data

    Vesna Cvetkov, Ilija Vasiljević, Mirko Petković (2015)

  • The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector

    Aleksandar R. Madžarević, Dejan D. Ivezić, Miloš L. Tanasijević, Marija A. Živković (2020)
    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 ...
    energetska bezbednost, prirodni gas, fazi AHP, AHP višekriterijumska analiza, fazi teorija
    ... system operators, PC Srbijagas, Novi Sad and joint stock company Yugorosgaz-Transport LLC, Niš. Natural gas distribution and distribution system operation are performed by 32 licensed distribution system operators. Most of them are owned by municipalities and towns, some of them are public-private partnership ...
    ... Length, km 18,422 Operating pressure for industry (medium pressure) 4–16 bar Length of distribution network at medium pressure ~1470 km Operating pressure for households (low pressure) <4 bar Length of distribution network at low pressure ~16,950 km * maximal daily capacity guaranteed by Hungarian ...
    ... Serbia there are 1 producer, 2 transmission system operators, 32 distribution system operators, 1 underground storage operator, 62 free market suppliers (30 are operational), 32 public suppliers simultaneously dealing with natural gas distribution and 1 supplier of public suppliers determined on the basis ...

  • Simulacija isticanja odabranih karstnih vrela pirotske kotline

    Saša Milanović, Branislav Petrović, Vesna Ristić Vakanjac, Ljiljana Vasić, Veljko Marinović, Petar Vojnović (2022)
    Analiza recesije, autokorelaciona i kroskorelaciona analiza vremenskih serija padavina i isticanja podzemnih voda karstnih vrela Krupac i Gradište (Stara planina, JI Srbija) izvršena je radi formiranja stohastičkog autoregresivno-krosregresivnog modela (ARCR) i kratkoročne prognoze dnevnih vrednosti izdašnosti. Usled postojanja heterogenosti i anizotropnosti karstne izdani veoma je komplikovano i zahtevno odrediti prostornu distribuciju podzemnih voda u okviru karstnog hidrogeološkog sistema, te je primenljivost determinističkih modela minimizirana. Stoga je upotreba stohastičkog modela u ovom slučaju svrsishodnija. Autokorelogram izdašnosti vrela Krupac pokazao je ...
    karstno vrelo, recesija, autokorelacija, kroskorelacija, ARCR MA model, JI Srbija

  • Projected changes in air temperature, precipitation and aridity in Serbia in the 21st century

    Boško Milovanović, Sebastian Schubert, Milan Radovanović, Vesna Ristić Vakanjac, Christoph Schneider (2021)
    У овој студији се испитују пројектоване промене средњих месечних и годишњих температура ваздуха, количине падавина и Де Мартоновог индекса аридности у Србији у 21. веку. У ту сврху статистички је моделована просторна дистрибуција температуре ваздуха и количине падавина на основу података 64 климатолошке станице и 421 падавинске станице за период 1976–2005 применом вишеструке линеарне регресије. Де Мартонов индекс аридности се израчунава из просторно распоређених података. Да бисмо добили регионалне просеке и варијабилност, Србију делимо на три поддомена: западну зону ...
    21 век, температуре ваздуха, климатске промене, Де Мартонеов индекс аридности, падавине, Србија

  • The influence of rainfall factors on soil resistance to erosion

    Nikola Živanović, Vukašin Rončević, Carla Ferreira, Milica Kašanin-Grubin, Stevan Ćorluka, Veljko Rupar, Vladimir Čebašek (2024)
    rainfall, rainfall factors, erosion, soil

  • Agates of the Lece Volcanic Complex (Serbia): Mineralogical and Geochemical Characteristics

    Zoran Miladinović, Vladimir Simić, Nenad Nikolić, Nataša Jović Orsini, Milena Rosić (2024)
    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 ...
    Lecki vulkanski kompleks, andeyit, kalcedon, kvarc, opal-CT, mikrostruktura, organska materija

  • 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
    ... recumbent folds F». In these hinge zones, S, is often folded into metre-size parasitic F, folds, whereas S, represents the axial-plane cleavage. As the foliation S, was observed only at hinges of folds F», its statistical distribution (Fig. 4b) reflects the geometry of limbs of large recumbent folds ...
    ... northern part of Vlasina Unit (22%757.756”E, 42%3/43.306"N). Size of the head of hammer 136 mm. c Fan- ning axial-plane cleavage So in the chlorite schists in the northern part of Vlasina Unit (22%18/15.775”E, 42%48'!21.52”N). Size of pen 152 mm. d Initial foliation S; folded in centimetre-scale ...
    ... Quartz grains show sweeping undu- lose extinction and deformation lamellae as well as evi- dence of dynamic recrystallisation predominantly by grain boundary migration (GBM) with less prominent evidence of subgrain rotation (SGR; Fig. 13b). Permo-Triassic Bujanovac pluton The Bujanovac magmatic ...

  • Synthesis and characterization of nanostructured Ca0.9Er0.1MnO3

    Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić (2023)
    ... in their appropriate stoichiometric ratios. Obtained Cao,Ero,,MnOx powder was calcined in a temperature range of 800-1000 *C for 15min. Particle size, lattice parameters, structural changes, and specific surface area were investigated. DTA, X-ray diffraction (XRD), FTIR, and Field emission scanning ...

  • Jeleč grad- još nepriznati objekat geonasleđa

    Marija Radisavljević, Danica Srećković Batoćanin, Vladan Vidosavljević, Irena Kajtez (2022)
    Остаци средњовековног града Јелеча на једном од врхова планине Рогозне (1262 m), по неким веровањима представљаju купу угашеног вулкана. Рогозна je позната по појавама скарновске Cu–Au минерализације, а трагови рударске активности и важних путева још од античких времена и даље постоје у непосредној околини. О томе сведочи и османски назив за Рогозну: Gümüş Dağ (Сребрна планина). Време изградње Јелеча је непознато. Постоје индиције да је постојао још у 6. веку, али се помиње први пут средином 12. века. Поуздан податак ...
    Rogozna, Jeleč, srednjevekovno utvrdjenje, kvarc latit, objekat geonasledja

  • Утицај обртног магнетног поља на дерацемизацију кристала натријум-хлората

    М. Милојевић, А. Жекић, П. Дабић, Б. Вучетић, Б. Максимовић (2023)
    ... rpm, |. – orientation of crystals is dominant, while at 600 rpm, D – orientation of crystals is dominant. X-ray structural analysis showed that the size of the lattice parameter of the obtained crystals does not depend on their oricntation and field rotational frequency, but only on its strength ...

  • VENTEX: An Expert System for Mine Ventilation Systems Analysis

    Ranka Stanković, Nikola Lilić, Ivan Obradović (1996)
    Analiza sistema za ventilaciju je komleksan proces, koji bazira na proračunu brojnih parametara, koji se odnose na: stanje mreže, provetrenost, stabilnost sistema, gubitke vazduha, klimatske uslove, gasno stanje, ugroženost od požara i opasne prašine. Navedeni problemi se uspešno rešavaju paketom SimVent, ali potpuno razumevanje i korišćenje dobijenih rezultata zahteva angažovanje iskusnog specijaliste iz oblasti ventilacije. Rešenje je nađeno u kreiranju ekspertnog sistema VENTEX, čija je baza znanja formalizacija ekspertskog znanja iz oblasti ventilacije rudnika. U radu je prikazana metodologija ...
    ekspertni sistem, ventilacija
    ... (Lilić, Stanković, and Obradović, 1994). This package, which enables the simulation of air flow distribution in a mine, the heat and fire transmission mechanisms, distribution of gas and distribution of respirable mineral dust, is currently being used by the “Soko” mine in Serbia. Numerical ...

  • FTIR spectroscopic study оf S-мetolachlor сorption оn inorganic and organically modified montmorillonite from Bogovina

    Lazar Kaluđerović, Zorica Tomić, Jelena Bogosavljević, Ljubomir Životić, Maja Milošević (2021)
    ... 333 SERBIAN SOCIETY OF SOIL SCIENCE Soils for Future under Global Challenges and C-N in this compound are in a conjugation mode due to the distribution of double bonds and lone electron pairs (Liu et al., 2002). š š š F| ž Ž\ š L š a% 3 NaM-SM E |Eg \' 'KN z a N2 _ :1 k a ____NM /V \gp ...
    ... on the oxygen of methoxy and ethoxy group are in resonance with the lone pair on nitrogen and the double C=O bond, which delocalizes the charge distribution and reduces the charge density on the carbonyl oxygen (Liu et al., 2000). The second significant change after the S-metolachlor sorption was detected ...
    ... 1021/jf010561p He, H., Zhou, Q., Frost, R.L., Wood, B.J., Duong, L.V., Kloprogge,J.T., 2007. A X-ray photoelectron spectroscopy study of HDTMAB distribution within organoclays. Spectrochim. Acta, Part A, 66, 1180—1188. DOI: 10.1016/J.saa.2006.06.005 Hladik, M.L., Roberts, A.L., Bouwer, E.J. 2006. ...

  • Actual contamination of the Danube and Sava rivers at Belgrade (2013)

    Milan Antonijević, Marija Arsović, Josef Cáslavský, Vesna Cvetković, Predrag Dabić, Mladen Franko, Gordana Ilić, Milena Ivanovic, Nevena Ivanović, Milica Kosovac, Dragana Medić, Slobodan Najdanović, Milica Nikolić, Jovana Novaković, Tatjana Radovanović, Djurdjina Ranić, Bojan Šajatović, Gorica Špijunović, Ivana Stankov, Jelena Tošović, Polonca Trebse, Olivera Vasiljević, Jan Schwarzbauer (2014)
    rečni sistemi, stanje zagađenja, organski zagađivači, teški metali, skrining analize, non-target screening
    ... spectrometer and electrospray ionization was used. The hormones were sepa- rated on a Phenomenex Kinetex C18 column, 100 Å, 150×3 mm, 2.6 μm particle size (Core- shell type) at a temperature of 25 °C using an acetonitrile (ACN)/water mixture at a flow of 0.25 mL min-1 (t0: 40 % of ACN, t20: 90 % of ACN) ...
    ... sediments accumulate persistent and toxic chemicals.11 In the past years, tremendous efforts have been made to characterize the fate, loading and distribution of heavy metals in sedi- ments.12 ___________________________________________________________________________________________________________ ...
    ... -estradiol, 17β-estradiol and 17α-ethinylestradiol were determined at the 20–200 pg L–1 level.46 Heavy metals in the sediments To exemplify the distribution and levels of sediment contamination by heavy metals in the Sava and Danube Rivers, the metals As, Cd, Cr, Cu, V, Pb, Ni and Zn were selected ...

  • Petrological and geochemical studies of lignite from the Tamnava West field, Kolubara basin (Serbia)

    Milena Pajić, Reinhard F. Sachsenhofer, Achim Bechtel, Ksenija Stojanović, Vladimir Krstić, Dragana Životić (2021)
    ... fraction in a low amount, while mono- and threearomatic triterpenoids are much more abundantin the aromatic fraction. Maceral composition and distribution of biomarkers of lignite from Tamnava West field imdicate high contribution of gymnosperm with variable contributioh of angiosperms in ...

  • A Lexical Approach to Acronyms and their Definitions

    Cvetana Krstev, Duško Vitas, Ranka Stanković (2015)
    In this paper we present a comprehensive approach to acronyms for Natural-Language Processing (NLP) of Serbian texts. The proposed procedure includes extraction of acronyms and their definitions that are usual Multi-Word Units (MWUs), shallow parsing of MWUs that enables MWU lemmatization and production of entries in morphological electronic dictionaries, both for MWU and acronyms, that are provided with grammatical, syntactic, semantic and domain information. This approach enables representation that reflects complex relations between acronyms and their definitions.
    ... required by morphological e-dictionaries, while e-dict_(MW|acr)_forms represent in- flected forms of MW names and acronyms, respectively. Input Size Output Size 1 corpus 23MW (acr., infl. def.)all 3,942 2 (acr., infl. def.)diff 2,163 foreign 96 manually 57 rejected 233 (acr., SWLs)diff 2,812 3 (acr ...
    ... . Moon, S., S. Pakhomov, and G. B. Melton, 2012. Auto- mated disambiguation of acronyms and abbreviations in clinical texts: window and training size considerations. In AMIA Annual Symposium Proceedings, volume 2012. American Medical Informatics Association. Pustejovsky, J., J. Castano, B. Cochran ...

  • Ventex: an expert system for mine ventilation systems analysis

    Nikola Lilić, Ranka Stanković, Ivan Obradović (1997)
    roblems relating to mine ventilation systems analysis are usually of a very complex nature. They involve the estimation of numerous interdependent parameters pertaining to the network status, ventilation status, ventilation system stability, air current losses, climate conditions, gas state, fire risk and dangerous dust pollution risk. The solution to these problems relies, to a great extent, on numerical methods. With the development of computer technology these methods were incorporated as numerical routes in software packages, such as the mine ...
    expert system, mine ventilation

  • Natural two-dimensional pyrophyllite: Nanoscale lubricant, electrical insulator and easily-machinable material

    Borislav Vasić, Radoš Gajić, Ivana Milošević, Žarko Medić, Marina Blagojev, Marko Opačić, Aleksandar Kremenović, Dejan Lazić (2022)
    Pyrophyllite, with the chemical formula Al2Si4O10(OH)2, is a naturally occurring and abundant van der Waals mineral belonging to the group of phyllosilicates. It is very soft, layered crystal used for sculpting and an excellent electrical and thermal insulator aimed for the operation at high pressure and temperature. Here, for the first time, two-dimensional (2D) pyrophyllite obtained by both mechanical and liquid phase exfoliation is presented and investigated at the nanoscale. The layered structure provides low friction coefficient of around ...
    Atomic force microscopy, Insulating properties, Nanofriction and wear, Natural two dimensional materials, Phyllosilicates, Pyrophyllite

  • 2D geoelectrical resistivity tomography application at the former city waste dump "Ada Huja": Eco-geological problem

    Branislav Sretenović, Filip Arnaut, Ivana Vasiljević, Vesna Cvetkov (2019)
    2D inversion, geoelectrical method, Wenner array, ecology, Ada Huja
    ... that indicate a high vertical resolution of the GPR equipment. 2D geoelectrical resistivity tomography … 65 Display of the sand lens distribution (Figure 6) as well as the marl basis can greatly help with getting a better understanding of the subsurface geometry. The sand lens is active ...
    ... shows again a decrease of thickness of the sand lens. The profile lines are at a mutual distance of 5 m. Figure 6 Display of the sand lens distribution through three parallel profile lines (I, II, III) part 4 (modified after Sretenović, 1998) 3D inversion results (Figure 7) obtained on six depth ...
    ... and the level of details. In addition to the good correlation between three mutually parallel profile lines (similar geometry and resistivity distribution), for the sake of confirmation and justification of the 2D geoelectrical scanning method, the root mean square value (RMS) should be viewed ...