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Упит dcterms_subject_txt:chemical composition

312 items

  • Some examples of interactions between certain rare earth elements and soil

    Zlatko Nikolovski, Jelena Isailović, Dejan Jeremić, Sabina Kovač, Ilija Brčeski (2021)
    Freundlich adsorption isotherm, sequential extraction, metallic ions, ICP-OES
    ... mineralogical composition and therefore as per physical and chemical properties. The soil preparation comprised cleaning from foreign bodes (twigs, leaves and stones), air drying for 7 days and following that determining the hygroscopic moisture content. Mineralogical soil sample composition was determined ...
    ... pharmaceutical and nuclear industry, metallurgy, electronics, medicine, chemical engineering1, agriculture2 and others has been on the upscale. The reason of their widespread use in important fields are their different chemical, electrical, magnetic, metallurgical, optical and catalyst properties.1 ...
    ... therefore these types of extractions are limited on it, namely this method is not so undemanding. The characteristics (composition) of soil, pH value and extraction solution composition Acce pted M anuscr ipt 10 NIKOLOVSKI et al. are particularly important for extraction effects. The suitability ...

  • Kristalne strukture Cs2HoSi4O10F i Cs2TmSi4O10F

    Predrag Dabić, Sabina Kovač, Aleksandar Kremenović (2021)
    ... rs During investigation focused on the synthesis of new potassium rare-earth elements silicates two compounds with a previously unknown chemical composition - Cs2HoSi4O10F and Cs2TmSi4O10F were obtained in form of single crystals. The compounds were synthesized by the method of crystal growth ...

  • 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

  • Sitni, ali bitni: uloga sitnih sisara, herpetofaune i mekušaca u rekonstrukciji pleistocenskih paleosredina

    Katarina Bogićević, Draženko Nenadić, Dragana Đurić, Mihajlo Jovanović, Aleksandra Savković (2023)
    Fosilni ostaci životinja i biljaka imaju važnu ulogu u rekonstrukciji pleistocenskih paleosredina. U ovom radu opisan je značaj tri grupe životinja: sitnih sisara, herpetofaune I mekušaca. Mada je za rekonstrukciju važan sastav čitave asocijacije, nalasci pojedinih vrsta mogu biti dovoljno indikativni da otkriju tip staništa ili klimatske uslove. Posebnu teškoću pri rekonstrukciji paleosredina u Srbiji predstavlja činjenica da klimatske promene na Balkanskom poluostrvu nisu bile tako oštre kao u srednjoj i zapadnoj Evropi, pa ne postoji drastična razlika u ...
    ... Pleistocene palaeoenvironments. This paper describes the importance of three groups of animals: small mammals, herpetofauna and molluscs. Although the composition of the entire association is important for reconstruction, the findings of individual species are sometimes sufficiently indicative to reveal ...
    ... the fact that climate changes on the Balkan Peninsula were not as sharp as in Central and Western Europe, so there is no drastic difference in composition, on the basis of which we would easily distinguish the fauna of the glacial and interglacial periods. Therefore, fine differences between associations ...
    ... c characteristics of the environment can also be obtained by geochemical studies of oxygen isotopes in mollusc shells. Analyzing the isotopic composition of shells from successive lineages can provide not only information on seasonal climate variations, but also data on global climate changes. ...

  • 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)
    ... in thc saturated 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 ...

  • Analysis and Calculation of MMRS and Primary Gas Distribution Network in Urban Environment – Case Study Kučevo

    Aleksandar Madžarević, Pavle Janković (2022)
    Oblast primene prirodnog gasa je veoma široka. Kao energent može se koristiti za proizvodnju energije u elektranama, toplanama i postrojenjima za kombinovanu proizvodnju energije ili za zadovoljavanje različitih toplotnih potreba u industriji i širokoj potrošnji. Gas se može upotrebiti i kao sirovina u hemijskoj i petrohemijskoj industriji, a tokom poslednjih decenija nalazi primenu i u saobraćaju kao pogonsko gorivo u SUS motorima. Sa ekološkog stanovišta, prirodni gas predstavlja najprihvatljiviji izvor energije u poređenju sa drugim fosilnim gorivima. Pri sagorevanju ...
    distribucija gasa, projektovanje gasovoda, analiza potrošnje

  • Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides

    Lazar Kaluđerović, Zorica Tomić, Rada Đurović-Pejčev, Maja Milošević (2021)
    ... onite samples from Bogovina (Serbia) were pretreated with 1M NaCl, and then with different concentrations of two organic complexes (HDTMA, PTMA). Chemical analysis of the sample showed that natural montmorillonite from Bogovina (Serbia) was Ca montmorillonite.  The whole modification process was ...
    ... Poster only Would you like to receive more information about applying for a grant once this becomes available?: Yes Content: The mineralogical composition of the soil clay fraction, along with soil organic matter, plays an important role in the sorption process of the soil. However, natural clay minerals ...

  • Investigation of Co0.9Ho0.1MoO4 Nanopowders Obtained by Glycine Nitrate Procedure

    Milena Rosić, Maja Milošević, Maria Čebela, Vladimir Dodevski, Vesna Lojpur, Radomir Ljupković, Aleksandra Zarubica (2023)
    ... estimated by the photocatalytic degradation of crystal violet in an aqueous solution. We present a simple and effective method for controlling the composition and morphology of CoooHooMoOu, as well as a possible new approach in inorganic synthesis methodology. During photocatalytic testing, the studied ...

  • 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
    ... performed by fuzzy composition, which is a model that provides the structure of indicators-influencing M performance. In other words, if the influence indicators A, B and C are presented as fuzzy numbers [20], their composition provides a fuzzy number which represents M. Max-min composition is often used ...
    ... synthesis, A, B and C parameters are synthesized into the M (Figure 4).Energies 2020, 13, x 9 of 15 Figure 4. Hierarchical structure of fuzzy composition. Partial indicators of optimal method of selection, A, B and C, are presented as membership function μ: A = (μA1,…, μAj,…, μAn); B = (μB1,… ...
    ... percentage overlap with some of the artificial lift methods represents the best solution for a new well. Figure 4. Hierarchical structure of fuzzy composition. Energies 2020, 13, 1758 9 of 15 The goal of this synthesis is to give a solution of optimization model. For example, if A1 is medium, A2 is ...

  • Geotehnički uslovi izgradnje tunela „Debelo brdo“ na autoputu E-80 Niš - Pločnik

    Dragoslav Rakić, Radojica Lapčević, Irena Basarić Ikodinović, Dragan Lukić (2022)
    Tunel „Debelo brdo“ nazvan je po najizraženijem relјefnom obliku na ovoj drugoj deonici autoputa E-80 Niš – Pločnik. Osnovnu geološku građu na lokaciji tunela čini Mio-Plioceni kompleks heterogenog litološkog sastava. Izgradnja tunela je predviđena delom u otvorenom iskopu dužine 240 m, a delom sa podzemnim iskopom dužine 190 m. U zoni tunela, padina je okarakterisana kao uslovno stabilna, pa bi neadekvatna zasecanja mogla da izazovu klizanja terena. Iz tih razloga, u okviru rada posebno su prikazani geotehnički uslovi izgradnje ...
    Tunel „Debelo brdo“, Geotehnički parametri, Privremene kosine, Šipovi, Podgrada.
    ... Plocnik highway. The basic geological structure at the location of the tunnel consists of the Mio-Pliocene complex of heterogeneous lithological composition. The construction of the tunnel is partly planned in an open excavation 240 m long, and partly with an underground excavation 190 m long. In the ...

  • 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
    ... river sediments | Snežana Štrbac, Gordana Gajica, Aleksandra Šajnović, Nebojša Vasić, Ksenija Stojanović, Branimir Jovančićević | Journal of Serbian Chemical Society | 2013 | | 10.2298/JSC130614087S http://dr.rgf.bg.ac.rs/s/repo/item/0002360 Дигитални репозиторијум Рударско-геолошког факултета Универзитета ...
    ... matter (OM) in recent sediments of the Tisza River, along a distance of 153 km through the territory of Serbia. For this purpose, group organic–geo- chemical parameters and biomarker compositions were used. All samples con- tained approximately same amount of OM, which was deposited under uni- form, slightly ...
    ... * Corresponding author. E-mail: ksenija@chem.bg.ac.rs; xenasyu@yahoo.com # Serbian Chemical Society member. doi: 10.2298/JSC130614087S ___________________________________________________________________________________________________ ...

  • Examination and characterization of nanostructured Co0.9Ho0.1MoO4

    Милена Росић, Маја Милошевић, Мариа Чебела, Владимир Додевски, Весна Лојпур, Марија Васић, Александра Зарубица (2023)
    ... synthesized by the glycine nitrate procedure (GNP) because it proved to be the most effective and simplest method suitable for controlling the composition and morphology of CoooHooiMoOua. To prepare nanostructured CoooHoo,MoOua, metal nitrates, and glycine were mixed in appropriate stoichiometric ...

  • The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)

    Marina Čokorilo Ilić, Ana Mladenović, Marina Ćuk, Igor Jemcov (2019)
    Geography, Planning and Development,Aquatic Science,Biochemistry,Water Science and Technology
    ... points were selected for chemical analyses of the water. Groundwater was sampled on three occasions and a total of 25 samples from the tunnel were analyzed (in some places sampling was not possible because the amount of water decreased over time). The primary chemical composition of the groundwater (HCO3 ...
    ... tical zones of the tunnel in terms of groundwater aggressiveness and the tunnel’s structural stability were identified on the basis of the chemical composition of the groundwater sampled from the tunnel. The aggressiveness analyses were based on EU standard EN 206-1 [13], US Department of Transportation ...
    ... pointed to the part of the tunnel where the concrete lining was unstable. Comprehensive tunnel investigations require the determination of the chemical composition of the groundwater that seeps into the tunnel. Hydrochemical data were used to examine their potentially aggressive properties, as well as ...

  • Mineralogical and physicochemical characterization of bentonite clay from Svrljig, Serbia

    Maja Milošević, Bojan Kostić (2022)
    ... properties is an important step to a potential technical application in the future. Characteristic properties of the sample were determined by chemical analysis, infrared spectrophotom- etry (Milošević and Logar, 2014; Milošević, 2011), differential thermal analysis (DTA) and X-ray diffrac- tion (powder ...
    ... and sand content were plotted on the triangular diagram, it was concluded that the sample is sandy clay with low porosity and low permeability. Chemical analysis showed that the sample mainly consists of 52.95% SiO2, 17.79% Al2O3, 1.02% K2O, 2.92% FeO, 6.34% CaO and 1.17% MgO, with a lower content ...
    ... approximately 900 °C and 300 °C corresponding to carbonates and iron oxy/hydroxides, respectively. The clay from Svrljig (Serbia) was characterized by chemical, mineralogical and thermal analysis. All applied methods were in good agreement indicating that the studied clay has a high content of montmoril- ...

  • A Model for Determining Fuzzy Evaluations of Partial Indicators of Availability for High-Capacity Continuous Systems at Coal Open Pits Using a Neuro-Fuzzy Inference System

    Miljan Gomilanović, Miloš Tanasijević, Saša Stepanović, Filip Miletić (2023)
    This paper presents a model for determining fuzzy evaluations of partial indicators of the availability of continuous systems at coal open pits using a neuro-fuzzy inference system. The system itself is a combination of fuzzy logic and artificial neural networks. The system availability is divided into partial indicators. By combining the fuzzy logic and artificial neural networks, a model is obtained that has the ability to learn and uses expert judgment for that learning. This paper deals with the ...
    системи, континуални системи експлоатације (роторни багер-транспортер-дробилично постројење), рударство, расположивост, меко рачунарство, фази логика, ANN, ANFIS

  • Post Early Miocenevertical-axis clockwise rotation in the West Vardar Zone of Serbia

    Vesna Lesić, Emo Marton, Vesna Cvetkov, Dragana Jovanović (2018)
    ... of Late Cretaceous micritic limestones and one locality of flysch and seventeen sites of Oligocene-Earliest Miocene igneous rocks of different composition. In the south, ın the wider Kopaonik Mts. Area we sampled cight sites of dacitoandesites andfifteen localities of granodiorites both of Oligocene ...

  • XRD dertermination od hydrothermal phases related to epithermal mineralization in the Čukaru Peki deposit

    Dragana Bosić, Vladica Cvetković, Miodrag Banješević, Kristina Šarić (2024)
    Čukaru Peki, epithermal mineralization, hydrothermal alterations

  • Synthesis, characterization and photocatalytic examination of Co0.9Ho0.1MoO4 nanopowders

    Milena Rosić, Maja Milošević, Maria Čebela, Vladimir Dodevski, Vesna Lojpur, Radomir Ljupković, Aleksandra Zarubica (2023)
    ... was estimated by the photocatalytic degradation of crystal violet in aqueous solution. A simple and effective . method for controlling: the composition and morphology of Cop.Hoo,, MoOu is presented in this paper, as well as a potentially new approach in the methodology of inorganic synthesis ...

  • Numerical modelling of the roughly simultaneous emplacement of two distinct ophiolite belts

    Nikola Stanković, Vesna Cvetkov, Vladica Cvetković (2024)

  • Површинско распадање керсантита из Тешића мајдана у корелацији са начином обраде на примеру малог степеништа (Београдска тврђава)

    Невенка Новаковић (2024)
    Архитектуру Београда на прелазу 19. у 20. век обележила је употреба керсантита из каменолома Тешића мајдана. Kao камен високих декоративних својстава, керсантит је коришћен за јавне споменике, делове или потпуну изградњу објеката (Народна скупштина Србије, Мало степениште, Народни музеј и др.). Како очување споменика културе изискује познавање својстава уграђеног камена, истраживања су обухватила детаљно проучавање петролошких, хемијских и физичких карактеристика керсантита из Тешића мајданa и узорака камена из споменика Мало степениште (студија случаја). Након детаљног мапирања стања керсантита, лабораторијских ...
    керсантит, Мало степениште, споменик културе, архитектонски камен, физичко-хемијско распадање, мапирање, форме распадања, површинска обрада