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Упит dcterms_subject_txt:space group

372 items

  • Flotability of chalcopyrite from the Rudnik deposit

    Đurica Nikšić, Predrag Lazić, Milena Kostović (2021)
    Директно селективно флотирање олова, бакра и цинка у флотацији рудника „Рудник” датира од 1984. године. Технолошка шема омогућава директно издвајање селективних концентрата у три циклуса. У првом циклусу се издваја минерал олова (галенит), док су минерал бакра (халкопирит) и минерал цинка (марматит) депримирани. У другом циклусу се оток концентрације минерала олова кондиционира и припрема за издвајање минерала бакра. Након кондиционирања, у овом циклусу се издваја минерал бакра. У трећем циклусу се оток концентрације минерала бакра кондиционира и припрема за ...
    Директно селективно флотирање, халкопирит, KAX, NaCN
    ... (chalcopyrite) and zinc mineral (marmatite) are depressed by NaCN. The lead mineral is extracted at pH from 8.8 to 9.2 by collector from the xanthate group (KAX). In the second cycle, the underflow of the lead mineral concentration is conditioned and prepared for the extraction of copper mineral. In ...
    ... regulation of pH is achieved by the addition of FeSO4. The copper mineral is extracted at pH values from 7.8 to 8.2 by collector from the xanthate group (KAX). Quality of copper concentrate obtained in flotation plant is very good. Average content of Cu in concentrate is 23.11% (minimum allowed content ...
    ... the zinc mineral is activated by the addition of CuSO4, and its extraction is performed at a pH of 11 to 12 by use a collector from the xanthate group (KAX). Ph regulation is achieved by the addition of CaO. NaCN is known to have a strong depressant effect on chalcopyrite, under appropriate conditions ...

  • Building learning capacity by blending different sources of knowledge

    Ivan Obradović, Ranka Stanković, Olivera Kitanović, Dalibor Vorkapić (2016)

  • Serbian Society of Geomorphologists

    Dragana Đurić, Jelena Ćalić (2019)
    ... о ће International Association of Geomorphologists (IAG). Additionally, the Society represented Serbia in the Carpathian-Balkan-Dinaric Working Group within the Carpatho-Balkan Geomorphological Commission (CBGC) (2012-2015). Society in the period 2011 - 2015 Subsequent to the foundation, the ...
    ... ofthe contributing chapter for ће international monograph “Recent Landform Evolution of the Carpatho-Balkan-Dinaric Region” within the CBD Working Group within the Carpatho-Balkan Geomorphological Commission (CBGC) (Pavlović et al, 2012). In 2013, on the 8th International Conference on Geomorphology ...
    ... 2016 the official website was promoted: www.geomorfologija.org.rs. In the same year, the Society received the first donation, by the company “Jantar group”. During 2016, multiple workshops and presentations related to geomorphology and SandBox practical work named “Relief — the origin and forms” were ...

  • Electronic Dictionaries - from File System to lemon Based Lexical Database

    Ranka Stanković, Cvetana Krstev, Biljana Lazić, Mihailo Škorić (2018)
    In this paper we discuss some well-known morphological descriptions used in various projects and applications (most notably MULTEXT-East and Unitex) and illustrate the encountered problems on Serbian. We have spotted four groups of problems: the lack of a value for an existing category, the lack of a category, the interdependence of values and categories lacking some description, and the lack of a support for some types of categories. At the same time, various descriptions often describe exactly the same ...

  • Asbestos-Based Pottery from Corsica: The First Fiber-Reinforced Ceramic Matrix Composite

    Philippe Colomban, Aleksandar Kremenović (2020)
    Asbestos-containing pottery shards collected in the northeast of Corsica (Cap Corse) and dating from the 19th century, or earlier, have been analyzed by SEM-EDS, XRPD, FTIR and Raman microspectroscopy. Blue (crocidolite) and white (chrysotile) asbestos fiber bundles are observed in cross-sections. Most of the asbestos is partly or totally dehydroxylated, and some transformation to forsterite is observed to occur, indicative of a firing above 800 C. Examination of freshly fractured pieces shows a nonbrittle fracture with fiber pull-out, consistent with ...
    asbestos, CMC, Corsica, fiber, pottery
    ... a rock rich in amphibole, is used as jade. Pyroxenes, e.g., diopside (CaMg((SiOy)»), also belong to the inosilicate group but exhibit a simpler composition, without the OH group. Orthopyroxenes have a more complex formula: (Mg.,Fe)>SiyOx. Jadeite, the second form of jade, has a composition close ...
    ... pyroxenes and belongs to the phyllosilicate group, like the serpentinites. XRPD patterns of samples a and b (Appendix A, Figures A1 and A?) are rather similar except for the identification of albite (sodium feldspar, belonging to the tectosilicate group) in both samples in place of orthopyroxene in ...
    ... frequent minerals are antigorite, chrysotile and lizardite. Five types of Materials 2020, 13, 3597 7of18 amphiboles, belonging to the inosilicate group but with rather similar composition (with orthorhombic or monoclinic unit-cells), are common and often associated with serpentinites: crocidolite ...

  • Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept

    Uroš Đurić, Miloš Marjanović, Zoran Radić, Biljana Abolmasov (2019)
    Improvements of Machine Learning-based landslide prediction models can be made by optimizing scale, customizing training samples to provide sets with the best examples, feature selection, etc. Herein, a novel approach, named Cross-Scaling, is proposed that includes the mixing of training and testing set resolutions. Hypothetically, training on a coarser resolution dataset and testing the model on a finer resolution should help the algorithm to better generalize ambiguous examples of landslide classes and yield fewer over/underestimations in the model. This ...
    klizišta, podložnost, mašinsko učenje
    ... the latter technique is that the instances that were not linearly separable in the original space can become linearly separable in a high-dimensional feature space, as constructed by transforming the original space Rn → Rω, ω> > n, so that instances are mapped as x→ x’ by the specific kernel function. The ...
    ... weight vector of x and b is its bias) as a separation line between landslide and non-landslide cases in the training input feature space. Let us consider a simple 2D feature space, with only two coordinate axes (herein, two landslide conditioning 5 http://mapa.urbel.com/beoinfo (13.04.2019.) 6 http://mapa ...
    ... margin M that lies between landslide and non- landslide instances in this space may be imagined wherein the instances on the margin are called Support Vectors. The best instance among all possible separating lines in a 2D feature space is the one that sits in the middle of the widest margin (M= 2/norm(w)) ...

  • Groundwaters of the "Valjevo karst" area (Western Serbia)

    Petar Dokmanović, Veljko Marinović (2021)
    “Ваљевски карст” је подручје кoje заузима површину од око 780 km2, док откривени кречњак чини око 330 km2. Припада Унутрашњим Динаридима западне Србије. У литостратиграфском погледу доминирају карстификовани кречњаци средњег и горњег тријаса у којима су формиране карстне издани. Анализирани су и систематизовани доступни подаци хидрогеолошких и других релевантних истраживања. Приказана је разграната мрежа траса подземних вода између понора и дренажних пунктова, као и главне карактеристике шеснаест карстних врела (или „разбијених“ дренажних зона) и девет (група) бунара, подељених ...
    карстнa издан, трасе подземних вода, извори, бунари, издашност, вишенаменско коришћење.

  • Development of the hybrid MCDM model for evaluating and selecting bucket wheel excavators for the modernization process

    Snezana Savkovic, Predrag Jovancic, Stevan Djenadic, Milos Tanasijevic, Filip Miletic (2022)
    This paper presents a methodology for evaluating and ranking different bucket wheel excavators (BWE) for determining which machine should enter in the process of revitalization and modernization. Various multicriteria methods are used. Combining them achieves the best effect when choosing BVE for the modernization process. AHP, TOPSIS, VIKOR, and PROMETHEE methods are used. The hybrid models are developed from the multi-criteria decision making (MCDM) methods and they are used to evaluate the basic indicators that characterize the operation of ...
    višekriterijumsko odlučivanje, rotorni bageri, modernizacija, ekspertska analiza

  • Characterization of bituminite in Kimmeridge Clay by confocal laser scanning and atomic force microscopy

    Paul C. Hackley, Jolanta Kus, João Graciano Mendonça Filho, Andrew D. Czaja, Angeles G. Borrego, Dragana Životić, Brett J. Valentine, Javin J. Hatcheries (2022)
    This work investigates bituminite (amorphous sedimentary organic matter) in Upper Jurassic Kimmeridge Clay source rock via confocal laser scanning microscopy (CLSM) and atomic force microscopy (AFM). These petrographic tools were used to provide better understanding of the nature of bituminite, which has been historically difficult to identify and differentiate from similar organic matter types in source rocks. As part of an International Committee for Coal and Organic Petrology (ICCP) working group, an immature (0.42% vitrinite reflectance), organic-rich (44.1 wt% ...
    Битуминит, Kонфокална ласерска скенирајућа микроскопија, Mикроскопија атомских сила, Органска петрологија, Термичка зрелост

  • Analiza nosivosti vertikalno opterećenog šipa za potrebe izgradnje petlje „Merošina 1“ na autoputu E-80 deonica: Niš – Merošina

    Dragoslav Rakić, Nikola Božović, Miloš Stevanović, Milan Bogdanović (2023)
    U Srbiji je počela izgradnja autoputa E-80 koji će predstavljati saobraćajno čvorište zapadnog Balkana i biće deo glavne regionalne transportne mreže jugoistočne Evrope. Njegova ukupna dužina kroz Srbiju iznosi 77 km, a prva deonica u dužini od 5.5 km je završena i puštena u saobraćaj krajem jula 2023. god. To je prva od četiri deonice Sektora 1 čija je dužina 32.65 km. U sklopu petlje „Merošina 1“ izgrađen je nadvožnjak koji je oslonjen na devet stubnih mesta na međusobnom ...
    petlja Merošina 1, šip, probno opterećenje šipa, projektni pristup, granična stanja

  • Novi pristup proučavanju tekstura minerala značajnih za istraživanje rudnih ležišta

    Aleksandar Pačevski (2022)
    ... razvoja Univerzitet u Beogradu – Rudarsko-geološki fakultet "Jelen Do" Lime & Aggregates - Carmeuse Group Rudarski institut d.o.o. Beograd IBIS-INŽENJERING d.o.o. Banja Luka Geoing Group GeoProspect d.o.o. VODAVODA Knjaz Miloš Kompanija Simex PLENARNA PREDAVANJA / PLENARY LECTURES ...

  • Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization

    Maja Todorović, Jana Štrbački, Marina Ćuk, Jakov Andrijašević, Jovana Šišović, Petar Papić (2016)
    ... different groups (clusters). Members of the result- ing groups are similar to each other but distinct from members of other groups. In this case, each group would represent a different hydrochemical type of mineral water, regarding differences in their physical and chemical characteristics. This hierarchical ...
    ... CO2 in the gas composition resulted in the presence of ele- vated concentrations of major and trace elements (highest median concentrations). This group included samples with the highest concentrations of individual ele- ments: Si (58.27 mg/L), K (113 mg/L), Li (5.72 mg/L), Rb (0.97 mg/L), Cs (0.71 ...
    ... samples taken from a spring originating from quartz–latites from the Rudnik volcanic area. C6 – Thermo-mineral waters Cluster C6 represents a group of mature Na–HCO3–Cl groundwaters with high TDS (up to 17,632 mg/L) and high temperatures formed in the Pannonian basin in the Vojvodina region ...

  • SASA Dictionary as the Gold Standard for Good Dictionary Examples for Serbian

    Ranka Stanković, Branislava Šandrih, Rada Stijović, Cvetana Krstev, Duško Vitas, Aleksandra Marković (2019)
    У овом раду представљамо модел за избор добрих примера за речник српског језика и развој иницијалних компоненти модела. Метода која се користи заснива се на детаљној анализи различитих лексичких и синтактичких карактеристика у корпусу састављених од примера из пет дигитализованих свезака речника САНУ. Почетни скуп функција био је инспирисан сличним приступом и за друге језике. Дистрибуција карактеристика примера из овог корпуса упоређује се са карактеристиком дистрибуције узорака реченица ексцерпираних из корпуса који садрже различите текстове. Анализа је показала да ...
    Српски, добри примери из речника, аутоматизација израде речника, издвајање својстава, Машинско учење

  • Influence of paleoenvironmental conditions on distribution and relative abundance of saturated and aromatic hydrocarbons in sediments from the NW part of the Toplica basin, Serbia

    Nikola Burazer, Aleksandra Šajnović, Nebojša Vasić, Milica Kašanin-Grubin, Dragana Životić, João Graciano Mendonça Filho, Predrag Vulić, Branimir Jovančićević (2020)
    Stratigraphy,Economic Geology,Geology,Geophysics,Oceanography
    ... distribution and relative abundance of DMCs (Zhang et al., 2008). It seems that DMC compounds with a methyl group on C-4 (C-5) may prevail in the saline conditions, while the others with a methyl group C-3 (C-6) are expected to be found in freshwater/swamp depositional environment. In accordance with the ...
    ... et al. Marine and Petroleum Geology 115 (2020) 104252 8 sporinite and alginite, especially lamalginite (Fig. 6f), dominates among the liptinite group, whereas bituminite is the least abundant liptinite maceral. Telalginite with yellowish fluorescence color is the most abundant type of alginite maceral ...
    ... values of the C/S ratio is observed (0.54–47.56, Table 6), referring to fluctuations in salinity (Meyers and Lallier-Vergès, 1999). Furthermore, a large group of studied samples demonstrates lower values of the C/S (under 10), which is common for the anoxic depositional environment (Berner and Raiswell, 1984; ...

  • 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

  • Definition of Circulation Conditions and Groundwater Genesis of the Complex Krupaja Hydrogeological Karst System (Eastern Serbia)

    Ljiljana Vasić, Saša Milanović, Tina Dašić (2023)
    Management, Monitoring, Policy and Law,Renewable Energy, Sustainability and the Environment, Geography, Planning and Development, Building and Construction
    ... drained. 3. Results The largest quantities of water are constantly being discharged from the Krupaja spring, which speleogenetically belongs to the group of deep siphonal springs, with a capacity that varies from 0.16 m?/s to over 31 mž/s. The second spring, of the investigated system involved thermal ...
    ... Suvodolska Banjica, at 6000 years old) [12]. The ionic composition of the Krupaja system water indicates that these are waters of the HCO{–CaZJr group. The content of Ca?* decreases with depth; the highest values were recorded at Krupaja Spring, ranging, from 3.92 to 52.39 mg /L. Slightly lower values ...
    ... ascend to the surface, which is supported by the groundwater age determined by the above-mentioned surveys of these waters. The channels of the t3 group are located much deeper than the cold water circulation zone and can be considered as a transition zone, that is, a mixing, zone with the oldest ...

  • Properties of fly ash and slag from the power plants

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    This paper describes the physical, chemical and mineral properties of ash and slag, which were taken from thermal power plants Nikola Tesla A, Nikola Tesla B, Kostolac A and Kostolac B. The knowledge of the mineralogical material composition is important because the type of minerals directly determines the properties of the fly ash and slag and their possible application. Laboratory tests showed that ash and slag samples consist of the following minerals: amorphous materials, quartz, feldspar, mullite, melilite, cristobalite, ...
    fly ash, slag, physical composition, chemical composition, mineral composition, X-ray diffraction method

  • Dvodimenzionalna geometrijska morfometrija prvih gornjih molara hominina sa teritorije Srbije - taksonomska i metodološka analiza

    Predrag N. Radović (2022)
    Primarni cilj ove studije tiče se taksonomske identifikacije fosilnih prvih gornjih molara (M1) hominina pronađenih u Srbiji, primenom metoda dvodimenzionalne (2D) geometrijske morfometrije. U prvoj (metodološkoj) fazi istraživanja ispitana je efikasnost 16 različitih pristupa (geometrijskih modela) u klasifikaciji M1 neandertalaca i anatomski modernog čoveka. Modeli su testirani na dva seta okluzalnih projekcija krunica (n = 34 i n = 64) dobijenih orijentisanjem digitalnih 3D modela u virtuelnom okruženju ili fotografisanjem fizičkih primeraka zuba. Prilikom testiranja primenjena je klasifikacija zasnovana ...
    2D geometrijska morfometrija, prvi gornji molar (M1), taksonomska identifikacija, neandertalci, anatomski moderni ljudi, Pešturina, Velika Balanica, Srbija

  • Kristalne strukture Cs2HoSi4O10F i Cs2TmSi4O10F

    Predrag Dabić, Sabina Kovač, Aleksandar Kremenović (2021)

  • Groundwater gravitational circulation of Karst Veliko Vrelo and Malo Vrelo springs by isotope and the noble gas method: case study of the Beljanica Massif

    Ljiljana Vasić, Laszlo Palcsu, Huang Fen (2019)
    Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry