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Упит dcterms_subject_txt:chemical analysis

808 items

  • A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers

    Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić (2019)
    Effectiveness evaluation is one of the basic components of engineering asset management and maintenance engineering in general. Effectiveness is an overall concept representing a measurement of quality of service level for the analyzed engineering system. This concept contains a series of partial indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model ...
    Efikasnost, Fazi zaključivanje, Prikupljanje podataka, Buldozer
    ... B1-F 0,16 0,18 0,23 0,24 0,20 B2-F 0,17 0,19 0,23 0,23 0,19 B3-F 0,16 0,18 0,22 0,23 0,20 4.3 Comparative Analysis of Results The comparative analysis of the results can be done on the base of data from tables 6 and 11, as well as from figure 11. The following conclusions can be ...
    ... indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model for their synthesis to the level of effectiveness. Mentioned data are ...
    ... behavior of the bulldozer during the operation and during the maintenance. The strength and applicability of the model were demonstrated by a comparative analysis of the obtained results. Keywords: Effectiveness, Fuzzy inference, Data collection, Bulldozer (Received on September 11, 2016; Accepted on December ...

  • Groundwater as an important resources in emergency situations of the Republic of Serbia

    Boris Vakanjac, Radoje Banković, Vesna Ristić-Vakanjac, Saša Milanović, Ljiljana Vasić, Saša Bakrač, Nikola Kozić (2024)
    Groundwater is a renewable resource wholly or partially protected from external influences (pollutants) by nature. Currently, about 75% of the population of the Republic of Serbia meets its water needs by using underground water. Hence, this water represents an essential strategic resource of our country; according to data from the Water Management Foundation of the Republic of Serbia (VOS, 2001), water from existing sources is used in quantities of about 23 m3/s. As 67.13 m3/s is the estimated potential ...
    podzemne vode, izvor, monitoring, vanredna situacija

  • ‘Blue-’ and ‘Brown-speckled’ pottery from Qalhât, the Sultanate of Oman (13–16th centuries): Comparison with traditional Omani 19–20 century productions

    Liliana Gianni, Hélène Renel, Aleksandar Kremenović, Philippe Colomban (2020)
    Representative ‘Blue speckled’ (13–16th centuries) and ‘Brown speckled’ (13–21st century) wares recovered from the excavations in Qalhât or collected around Bahlâ city (Sultanate of Oman) were characterized by XRPD, SEM-EDS, Raman/optical microspectroscopy, and thermal expansion. Minerals present in the body (quartz, augite and albite as major phases, calcite, dolomite, rutile, anatase, phosphate, hematite and magnetite as minor phases) were identified by XRPD and/or Raman spectroscopy. SEM-EDXS microanalysis was performed on the glazes in order to compare their composition, especially ...
    Firing, Glaze, Traditional ceramics, Provenance studies, Augite

  • SrpELTeC: A Serbian Literary Corpus for Distant Reading

    Ranka Stanković, Cvetana Krstev, Duško Vitas (2024)
    U članku je predstavljen SrpELTeC, korpus razvijen u okviru akcije COST Distant Reading for European Literary History (CA16204). Svi romani u SrpELTeC-u su odabrani, pripremljeni i obeleženi korišćenjem zajedničkih principa uspostavljenih za sve jezičke zbirke u Evropskoj zbirci književnog teksta (ELTeC). Navedeni su izazovi i rešenja u pripremi SrpELTeC od nule. Svi romani su ručno kodirani u TEI sa bogatim metapodacima i strukturnim napomenama. Automatska anotacija je uključivala POS-označavanje, lematizaciju i imenovane entitete, oslanjajući se na resurse za obradu ...
    digital humanities, Serbian literature, text corpora, distant reading , linked data, named entity recognition, text analytics

  • Applicability of the risk ranking methodology designed for water reservoirs to tailings storage facilities

    Dragana Nišić, Dinko Knežević, Aleksandar Cvjetić, Neda Nišić, Vladimir Jovanović (2022)
    The risks associated with operating water reservoirs and tailings storage facilities (TSFs) are different because of their different purposes, methods of construction and operation, and characteristics of the materials impounded and their flow behaviour. Regardless of the differences, these two types of structures are often put in the same category when it comes to risk assessment and the application of relevant methodologies, which may result in unrealistic outcomes. In this paper we investigate whether it is possible to apply ...
    procena rizika, akumulacije za vodu, jalovište, TSF, ICOLD, FMEA

  • Application of the PROMETHEE and VIKOR methods for selecting the most suitable carbon dioxide geological storage option

    Lola Tomić, Vesna Karović Maričić, Dušan Danilović, Branko Leković, Miroslav Crnogorac (2019)
    CO2 storage in geological formations is one of the leading solutions for mitigation of greenhouse gas emissions. Types of geological formations that can be used for CO2 storage, that are discussed in this paper are: depleted oil and gas reservoirs, saline aquifers and injection CO2 in partially depleted oil reservoirs for enhanced oil recovery (EOR–CO2 method). In order to select the most suitable geological storage of CO2, the ranking of these storage options was performed using two methods of ...
    Prometej, vikor, višekriterijumsko odlučivanje, geološko skladištenje

  • Effect of natural gas composition on methane number: A case of gas reservoirs in Serbia

    Marija Živković, Milica Ivić, Dejan Ivezić, Aleksandar Madžarević (2017)
    Natural gas is considered as the most environmentally acceptable fossil fuel, thus it is an alternative to petroleum derivate, dominantly used in internal combustion engines. Physical properties of a fuel as well as behavior during combustion process are affected by its composition. This article presents analysis of effect of natural gas composition on methane number (MN), conducted for natural gas deposits in Serbia. For empirically determination of MN: California air resources board (CARB) method and Linear and Anstalt für ...
    Састав, метански број, природни гас

  • Synthesis of MnCo2O4 nanoparticles as modifiers for simultaneous determination of Pb(II) and Cd(II)

    Vesna Antunović, Marija Ilić, Rada Baošić, Dijana Jelić, Aleksandar Lolić (2019)
    The porous spinel oxide nanoparticles, MnCo2O4, were synthesized by citrate gel combustion technique. Morphology, crystallinity and Co/Mn content of modified electrode was characterized and determined by Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction pattern analysis (XRD), simultaneous thermogravimetry and differential thermal analysis (TG/DTA). Nanoparticles were used for modification of glassy carbon electrode (GCE) and new sensor was applied for simultaneous determination of Pb(II) and Cd(II) ions in water samples with the ...
    MnCo2O4 nanočestice, modifikatori, određivanje Pb (II) and Cd(II)

  • Дефинисање механичких својстава алтерисаног стенског материјала лабораторијским методама

    Вељко М. Рупар (2022)
    Основни циљ овог рада је да представи методологију одређивања механичких својстава хетерогеног стенског масива који изграђују дацит (Д) и алтерисани дацит (АД), где је уочена је зона постепеног преласка од алтерисаног дацита до дацита. Механичка својства стенског масива у тој зони утврђена су на основу лабораторијских испитивања једноосне и троосне чврстоће на притисак стенског материјала композитних узорака. Композитни узорци су се састојали од дискова стенског материјала, при чему је висина дискова h дефинисала различити процентуални удео појединог стенског материјала, ...
    дацит, алтерисани дацит, једноосна чврстоћа на притисак, троосна чврстоћа на притисак, композитни узорци, механика стена, стабилност косина

  • Model of the Geomagnetic reference field of the Republic of Serbia

    Spomenko J. Mihajlović, Vesna Cvetkov (2024)

  • Production information system of the Pljevlja coal mine

    Božo Kolonja, Ranka Stanković, Filip Vuković (2018)
    ... periodic reports to support the planing and monitoring trends; exception reports for identification of problems; on-request reports for production analysis. The outlined system is designed to provide information for decision making personal on minesite. 1 INTRODUCTION The challenge information ...
    ... budget, control of this costs is an important aspect of mine managment. An effective cost control program must include up- to-date feedback and analysis of expenditures. A work order system is the most common means of capturing the various costs as they are incurred. Combined with production data ...
    ... of mining equipment, which is displayed in Figure 1 by shaded rectangles. Figure 1. Business system of an open pit mine 3 SYSTEM ANALYSIS The complexity of business dealings requires the use of CASE tools, which support the complete development cycle: process modeling, conceptual ...

  • The influence of Al<sup>3+</sup>ion on porcine pepsin activity<i>in vitro</i>

    Vesna M. Pavelkić, Kristina R. Gopcević, Danijela Z. Krstić, Marija A. Ilić (2008)
    The in vitro effect of Al3þ ions in the concentration range 1.7·1026M–8.7·1023M on pepsin activity at pH 2, via kinetic parameters and its electrophoretic mobility was evaluated. Kinetic study demonstrated the existence of an activation effect of Al3þ at pH 2 on pepsin molecule. Kinetic analysis with respect to concentrations of haemoglobin showed that Al3þ ions increase the maximal velocity (Vmax) and kcat values rather than apparent affinity for substrate (KS) implying the non-competitive nature of activation which indicated ...
    Пепсин, алуминијум, кинетика, активација, електрофоретска мобилност
    ... ions on the activity of extra- cellular enzymes is scant and controversial. Variability of data results from the chemical properties of the element and the formation of various chemical species, depending on the pH, ionic strength, presence of competing elements and complexing agents within the ...
    ... ICP, 2.5 kV"w, 27 MHz). ICP-AES analysis was performed by measuring. the intensity of radiation of the specific wavelength emitted by aluminium at 396.152 nm and with a sample flow rate of 1 mL min '. Integration times were 1 per increment (.e., analysis time of 1 minute per sample). UYV ...
    ... dye migration]| (2) Statistical analysis Graphs were plotted by using Microcal Origin program (version 6.1). Values including Ks, Vnas= Kos» KnA» KAa, and Aaso and their standard errors are presented as means + SEM (obtained by the linear regression analysis). The statistical comparisons were ...

  • Analysis Of the Process Of Carbon Capture Utilization And Storage In Underground Reservoirs

    John Nyame (2024)
    The importance of mitigating the effects of global climate change has necessitated an in-depth exploration of innovative strategies to reduce carbon dioxide (CO2) emissions. Among these strategies, Carbon Capture, Utilization, and Storage (CCUS) has emerged as a promising and transformative solution. This master thesis delves into the diverse realm of CCUS processes, aiming to unravel the positives challenges, and opportunities within this dynamic field. The analysis begins with a systematic examination of carbon capture technologies, encompassing post-combustion, pre-combustion, and oxy-fuel combustion ...
    Carbon Capture, Utilization and Storage
    ... CARBON CAPTURE ANALYSIS Carbon capture is the process of trapping carbon dioxide from fossil burning or industrial (chemical) processes in preventing the carbon dioxide from affecting the atmosphere with the goal to mitigate effects of climate change [6]. Carbon capture analysis is an essential ...
    ... AAAAA AAAAAA RAAAAAA RAAAAAA AAAAAA AAAAAA RAAAAAA RAAAAARAAAAAVAA 15 3. CARBON UTILIZATION ANALYSIS 3.1. Desalination of Captured CO» 3.2. Enhanced Oil Recovery ... 3.3. Mineralization 3.4. Chemical Conversion.aaaaaaaaaaaaaaaaaaaaaaaeaaaaaaaaaeaaaaeaaaaaaaaaeaeaaeaeaaaaeaaaaeaaaaeeaaeaeaaaa ...
    ... goases ·'· - J @·Ubt iil | |j | Figure 2.5 CO- separation using membrane material. _2 « Feed gas 55"C «~ e • ~ •a 2.4. Chemical Looping Chemical looping can be potentially cost-effective CO--capture options with minimum energy losses, in which both CO- and H»O are inherently separated ...

  • Concentracion possibility examination of ore from „Ćulav Brajšor” field, near Medveđa

    Đurica Nikšić, Predrag Lazić, Branko Zečević (2017)
    У раду су приказани резултати лабораторијских испитивања могућности концентрације Pb-Zn-Au-Ag руде са локалитета „Ћулав Брајшор“ из околине Медвеђе. Резултати су добијени током израде студије могућности концентрације ове руде, а у оквиру израде елабората о резервама за ово лежиште које је радила фирма Металфер д.о.о. из Сремске Митровице. На основу резултата лабораторијских испитивања може се рећи да се ради о веома флотационој руди која даје изванредне квалитете концентрата олова и цинка. У концентрату олова добија се висок садржај злата ...
    флотацијска концентрација, квалитет концентрата, искоришћење

  • Correlability of Solar Wind with Seismic Events in the Balkan Peninsula Zone

    Filip Arnaut, Dejan Vučković, Ivana Vasiljević, Vesna Cvetkov (2021)
    The Solar Heliospheric Observatory (SOHO) satellite was launched on the 2nd of December 1995 at L1 Lagrange point (1.5×106 km from Earth) with the purpose of gathering data for helioseismology, remote sensing of the solar atmosphere, and solar wind in situ. The satellite was positioned into orbit in early 1996, with data acquisition expected to commence on January 20th. The correlation between increased values of solar wind parameters and earthquakes in the Balkan peninsula zone between 1996 and 2018 ...
    предвиђање потреса, соларни ветар, статистичка валидација узрочника потреса

  • Hydrochemical impact of the hydraulic tunnel on groundwater in the complex aquifer system in Pirot, Serbia

    Marina Ćuk, Igor Jemcov, Ana Mladenović, Marina Čokorilo Ilić (2020)
    Hidrogeohemijski procesi, hidrohemijske promene, karstna izdan, tunel pod pritiskom, multivarijantne statističke analize

  • 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
    ... 1911) were determined according to the Casagrande method (Laboratoire Central des Ponts et Chaussées, 1987). Results and discussion Chemical composition Chemical analysis of the samples (Table 1) shows a relatively large abundance of SiO2 (>61 wt.%) and Al2O3 (16–19 wt.%), a total Fe2O3 content of 2–4% ...
    ... Kamseu et al., 2007). Fe2O3, TiO2 and Na2O are more abundant in the uppermost sample (#6) than in the lowermost sample (#3; Table 1). Table 1. Chemical analysis of the samples (wt.%). Sample SiO2 Al2O3 Na2O K2O CaO MgO Fe2O3 a TiO2 MnO LOI Total 6 64.80 18.07 1.13 0.91 0.42 0.03 4.42 0.90 0.02 9.19 99 ...
    ... obtained by XRF analysis. A few irregular Fe oxide grains of rounded shape have also been observed in sample 4. Fig. 5. Ternary diagram of the samples showing the relationship between clay, silt and sand (after McManus, 1988; Strazzera et al., 1997). Clay Minerals 373 Thermal analysis The DTA curves ...

  • Investigation of nanostructured Ca0.9Er0.1MnO3 obtained by sucrose nitrate procedure

    Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić (2023)
    ... structure. The resulting: CapEro,, MnOxy is calcined for 15 minutes in the temperature range from 800% to 1000%. Diffraction thermal analysis (DTA), X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and inductively coupled plasma ICP were ...
    ... influence of geometry on the determination of the stress intensity factor KI on specimens produced by the selective laser sintering technique.The analysis of the determination of the stress intensity factor includes experimental and numerical tests. For this purpose, two geometries of specimens were ...

  • A new polymorph of Ba(AsO3OH): Synthesis, crystal structure and vibrational spectra

    Tamara Đorđević, Ljiljana Karanović (2010)
    A new monoclinic polymorph of Ba(AsO3OH) was synthesized under hydrothermal conditions. It represents a previously unknown structure type. Its crystal structure was determined from a racemic twin using single-crystal X-ray diffraction data collected at 120 and 293 K [space group P21, a=7.2149(14)/7.2370(2), b=7.7028(15)/7.7133(2), c=21.7385(43)/21.8079(5) Å, β=95.95(3)/96.073(1)1, V=1201.6(4)/1210.51(5) Å3, Z=12]. The crystal structure of P21-Ba(AsO3OH) has a layered character and is built up of four types of regularly alternating layers parallel to (0 0 1). Every AsO3OH tetrahedron is chelating to two Ba atoms and ...
    Ba(AsO3OH), хидротермална синтеза, структурна анализа монокристала, Раманска спектроскопија, инфрацрвена спектроскопија, водоничне везе, хидрогенарсенати земноалкалних метала

  • Dating of alluvial sediments from borehole at the lower course of the Sava river and indications of the connection between their genesis and climate changes in the Pleistocene

    David Mitrinović, Jelena Zarić, Oliver Anđelković, Gyorgy Sipos, Dušan Polomčić, Milan Dimkić (2019)
    This paper analyses the way in which Pleistocene climate change and glaciations in Dinaric Mountains was reflected in the deposition of alluvial sediments in the Sava river Valley, using a case study of Belgrade Groundwater Source (BGS), the largest and most downstream alluvial water supply source along the Sava river. A stratigraphic analysis of the Quaternary sediments from two boreholes on this site, based on sediment dating, lithological members identification, grain size distribution analysis was performed. Comparison with the ...
    Pleistocene, Alluvial deposits, Climato-lithostratigraphy, Sava river, Belgrade groundwater source, Luminescence