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Упит dcterms_subject_txt:phase composition

313 items

  • 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. ...

  • The Many Faces of SrpKor

    Duško Vitas, Ranka Stanković, Cvetana Krstev (2024.)
    Акроним СрпКор означава фамилију електронских корпуса савременог српског језика чија је изградња почела крајем седамдесетих година прошлога века, а која је постала шире видљива заинтересованој истраживачкој заједници објављивањем његове прве верзије на вебу 2002. године. У овом дугом периоду, посебно пре појаве корисних текстуелних ресурса на вебу, развој корпуса се састојао у прикупљању и обради грађе као и у развоју метода обраде корпуса. Наиме, електронски корпус није само колекција текстова у дигиталном облику (како се то, на пример, наводи ...
    СрпКор, корпуси, српски, лематизација, Лексимирка

  • 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

  • Non-Detonating Chemical Mixture for Non-Invasive Methods of Rock Breaking

    Lazar Kričak, Milanka Negovanović, Nikola Simić, Stefan Milanović (2024)
    Within the Innovation developed several different non-detonating chemical mixtures for non-invasive methods of rock breaking. Laboratory and polygon tests gave the satisfactory results and knowledge enough to start the practical experiments in the field. The basis of this innovation is a theoretical assumption that certain chemical mixtures release a large quantity of gases during combustion. If these gases are found in the enclosed space a growing pressure on the walls of the chamber in which combustion takes place will ...
    non-detonating, chemical mixture, rock breaking, borehole pressure

  • 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)
    ... 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 ...

  • Solid state synthesis of extra phase-pure Li4Ti5O12 spinel

    Ivana Veljković, Dejan Poleti, Ljiljana Karanović, Miodrag Zdujić, Goran Branković (2011)
    Фазно чист спинел Li4Ti5O12 са величином честица мањом од 500 nm добијен је реакцијом у чврстом стању из стехиометријске смеше наноанатаса (ТiО2) и Li2CO3 која је претходно активирана механохемијским поступком. Реакција у чврстом стању у потпуности се завршава за само 4 часа на температури од 800 ºC. Уз помоћ XRPD, SEM и TG/DSC анализе испитане су структурне и микроструктурне карактеристике добијеног спинела, механизам реакције између анатаса и Li2CO3, као и термичка стабилност Li4Ti5O12. Реакција започиње разлагањем Li2CO3 на температурама ...
    дифракција рендгенских зрака, механизам реакције, термичка стабилност, Li4Ti5O12, спинел, фазно чист узорак

  • Unusually sluggish microemulsion system with water, toluene and a technical branched alkyl polyethoxylate

    Marija Ilić, Franz-Hubert Haegel, Vesna Pavelkić, Snežana Zlatanović, Zoran Marković, Aleksandar Cvjetić (2015)
    Microemulsion systems with water, toluene and nonionic surfactants are interesting for application due to the excellent solvent properties of aromatic hydrocarbons. In this study, the pseudo-binary phase diagram (“fish-diagram”) of such a ternary system was investigated using a branched technical alkyl polyethoxylate. Lutensol ON 50 (i-C10E5) was considered a suitable surfactant. The system with technical branched i-C10E5 exhibits very long, and for compositions near optimum solubilization, i.e., the minimum content of surfactant needed for a bicontinuous microemulsion, extremely long ...
    микроемулзија, толуен, оксоалкохол етоксилат, термодинамичка стабилност, тернарни фазни дијаграми, дијаграми „fish“

  • 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
    ... biomarkers as a kind of “finger- print”, which depends on the origin, depositional environment, age, maturity, relative length of migration and mineral composition of the source and reservoir rocks.10,11 This feature of oil can be very useful in environmental chemistry for the determination of the source of ...
    ... <0.1 0.07 6.5 6.2 87.3 M6 1.29 0.10 <0.1 0.11 6.9 3.4 89.7 M4 1.66 0.13 <0.1 0.08 3.3 3.7 93.0 M5 1.36 0.09 <0.1 0.09 3.6 4.6 91.8 Molecular composition of the organic matter n-Alkanes and isoprenoids. All samples showed very similar distributions of n-alkanes and isoprenoids. The n-alkanes were ...
    ... “fingerprint”, which in addition to maturity, depends on the origin, depositional environment, age, relative length of migration and the mineral composition of the source and reservoir rocks. Therefore, crude oils can significantly differ in values of source parameters, such as distribution of C27– ...

  • 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 ...

  • Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete

    Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović (2021)
    sagorevanje lignita, otpadna šljaka, zamena cementa, proizvodnja maltera i betona, fizičko-mehanička i fizičko-hemijska karakterizacija
    ... spectroscopy (FTIR), field emission scanning electron microscopic analysis (FESEM), and thermal analysis. The structural properties and the composition of the crystal phase of the hardened mortar samples were determined by the XRD. For analysis, a PW-1710 X-ray diffractome- ter (Philips, Amsterdam, Netherlands) ...
    ... (Ca(OH)2), quartz (SiO2), calcite (CaCO3), and calcium silicate-oxide (Ca2SiO4). The most abundant phase was quartz, then portlandite, and calcite, while calcium silicate- oxide was less present. Such composition was expected because portlandite, calcite and calcium silicate-oxide originated from cement, while ...
    ... bought from the company CRH Popovac, Serbia. Silica fumes were bought from the company “Sika”. The physical–chemical, chemical and mineralogical composition of the used cement, slag and silica fumes are given in Table 1. Table 1. The physical–chemical, chemical and mineralogical properties of the used ...

  • 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
    ... operation (Phase B). Phase A illustrates the state when the tunnel and the hydrogeologic environment were under pressure, while phase C reflects the state when only the tunnel was under pressure. Table 1. Observation periods. Phase Tunnel Mode Beginning–End of Observation Duration of Phase A Tunnel ...
    ... at observation well PP-3, Table 2. Table 2. Changes in water levels in the reservoir and observation wells PP-1 and PP-3, by operating phase of the tunnel. PHASE A B C A ∆S(m)/Reservoir 1.48 0.92 1.01 4.78 ∆S (m)/PP-1 0.76 3.18 0.51 2.85 ∆S (m)/PP-3 3.18 43.03 42.14 2.85 However, despite the fact ...
    ... 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 −, Cl−, SO4 −, Na+, K+, Ca2+, Mg2+) was determined by standard analytical methods under laboratory conditions. Potentially ...

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

    Maja Milošević, Bojan Kostić (2022)
    ... of 16%, CEC (84.5 mmol/100g) and SSA (661.8 m2*g–1) indicate a higher content of montmorillonite. Infrared spectrophotometry determined that the composition corresponds to a high content of montmoril- lonite clay with peaks at 3620 cm–1, 3420 cm–1, 1632 cm–1 and 1018 cm–1. The peaks at 1444 cm–1 and ...

  • 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

  • Синтеза и карактеризација керамике на бази сфена

    Jelena R. Pantić (2015-07-10)
    Механохемијска активација стехиометријске смеше реактаната TiO2, SiO2 и CaCO3 показала се као веома успешна и једноставна метода за добијање сфена (CaTiSiO5). На основу мерења релативних густина свих синтерованих узорака установљено је да максималну густину од 93,9 % имају узорци који су активирани 30 минута и синтеровани на 1200 °С. Микроструктурном анализом, тј. анализом слика синтерованих узорака активираних 30 минута, које су добијене скенирајућом електронском микроскопијом, опажа се бимодална расподела величине зрна, са просечном величином од 3 μm, односно 5 ...
    сфен, механохемија, Ритвелдова метода, оптичка спектроскопија, микроструктурна анализа, фазна трансфоpмација, чврсти раствори
    ... аѕ a principle crystalline phase. The most important structural change due to phase transition, the disappearance of the characteristic out-of-center distortion of the Ti atom and moving to the center of octahedra, was also confirmed via Rietveld refinement. Phase transition from P21/a to A2/a ...
    ... space group P21/a аѕ a principle crystalline phase. The other two phases (perovskite and coesite) are present at all temperatures indicating its minor amounts. Quantitative analysis was calculated from the Rietveld refinement. Percentage of each phase is 93.3 % for sphene, 2.9 % for perovskite ...
    ... Am Mineral 84: 282-287. Angel R.J., Kunz M, Miletich R., Woodland A.B., Koch M. and Xirouchakis D. (1999b) High pressure phase transition in CaTiOSiO4 titanite. Phase Trans 68: 533-543. Angel R.J., Ross N.L., Seifert F. and Fliervoet T.F. (1996) Structural characterization of pentacoordinate ...

  • 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