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Упит dcterms_subject_txt:niska temperatura

402 items

  • 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
    ... of production is translated into grades. Parameter B3 represents the temperature. Based on the optimal and maximum fluid temperature at which each of the observed artificial lift methods can be applied, the higher the temperature of the fluid, the fewer the methods that can be applied. Parameter B4 ...
    ... 8–267 18–5343 53–712 18–1781 0.89–392 Maximum operating volume (m3/d) 1069 7124 2672 5343 801 Typical operating temperature (◦C) 38–177 38–135 38–121 38–121 24–66 Maximum operating temperature (◦C) 288 204 260 204 121 Corrosion handling Good to Excellent Good Excellent Good to excellent Fair Gas handling ...
    ... of the well, and characteristics of the reservoir. The second step further reduces the choice, based on secondary technical limitations, such as temperature limitations, operator training, availability of the main source of energy, fluid, surface conditions (space limitations, noise, visibility, safety) ...

  • Trans-Lithospheric Diapirism as a Possible Mechanism for Ophiolite Emplacement?

    Nikola Stanković, Taras Gerya, Vladica Cvetković, Vesna Cvetkov (2024)

  • Mikroorganizmi - biohidrogeološki indikatori odabranih pojava mineralnih voda Srbije

    Vladimir Šaraba (2021)
    Sa namerom definisanja hidrogeološke uloge i značaja mikrobiološkog diverziteta odabranih pojava mineralnih voda Srbije, primenom sistema biodetektora, dokazano je prisustvo gvožđevitih, sulfato-redukujućih, sluz-produkujućih, heterotrofnih aerobnih i denitrifikacionih bakterija, na osnovu čega je proračunat rizik od razvoja procesa biokorozije i biohemijske inkrustacije, te zdravstveni rizik. Uz procenu rizika, izvedene su analize skenirajuće elektronske mikroskopije biofilmova i hidrogeohemijsko modeliranje, te makroskopska, otpička i difrakciona ispitivanja naslaga inkrustacije, dok je fizičko-hemijskim analizama utvrđena vrednost ukupne mineralizacije iznad 1 g/L, kao i povišeni ...
    biohidrogeologija, SEM analize, makroskopska i optička ispitivanja, rendgenska difrakcija praha, hidrogeohemijsko modeliranje, BART analize, metabarkoding analize mikrobioma, fizičko-hemijske analize, starenje bunara (biokorozija, biohemijska inkrustacija i biozarastanje), zdravstveni rizik
    ... raste na temperaturi -12°C, najnižoj temperaturi za bilo koju poznatu bakteriju. Organizmi koji rastu na 0°C, ali imaju optimalnu temperaturu razvoja od 20-40°C, nazivaju se psihrotolerantni mikroorganizmi i rasprostranjeniji su u prirodi u odnosu na psihrofile. Razvijaju se i na temperaturi od 0°C ...
    ... pokretljivost (migraciju) Uticaj na opstanak Uticaj na pokretljivost(migraciju) Temperatura Opstanak virusa je znatno duži na nižim temperaturama Nepoznato Opstanak bakterija je znatno duži na nižim temperaturama Nepoznato Aktivnost mikroorganizama Neko virusi se lakše inaktiviraju u prisustvu ...
    ... poseduju mehanizme za održavanje temperature ćelije. Poznato je da na visokim temperaturama nukleinske kiseline, belančevine i drugi delovi bakterijske ćelije se mogu bespovratno inaktivisati, usled čega dolazi do smrti ćelije. S druge strane, pri niskim temperaturama dolazi do zaustavljanja bakterijskog ...

  • A hundred years of Milutin Milanković's climate change theory - geological implications

    Dejan Radivojević (2020)
    Миланковићева теорија циклуса објављена пре сто година је најважнија теорија у наукама које проучавају климу и имала је велики утицај на дисциплине које се баве Земљом. Ипак, његов рад је чекао више од педесет година да би добио потврду. Може се рећи да Миланковићев рад највећи утицај на геологију има у изради астрономске временске скале, подршци хипотези континенталног дрифта и палеоклиматологији. Добри резултати примене астрономске временске скале на неогене седименте иницирали су примену ове методе у мезозојским и у последње ...
    циклостратиграфија, астономска временска скала, геолошка временска скала, климатске промене, континентални дрифт
    ... ocene temperature maximum (PETM) is of special importance for climatologists since it represents the excellent analogue for climate prediction modelling. The PETM is marked by a short (100.000 years) clear drop in value associated with sudden warming and was marked by the high- est temperature during ...
    ... change theory – geological implications Geol. an. Balk. poluos., 2020, 81 (2), 87–98 95 Fig. 9. The global temperature trend during the Cenozoic (65 Ma). There is a significant temperature drop (about 14°C) from the end of the Paleocene toward the Pleistocene Glaciation. (PETM - Paleocene-Eocene thermal ...
    ... Results of Leg 189. JoidES Journal, 26 (2):11–18. FERGUS, G. 2015. Temperature of Planet Earth. Retrieved from http://gergs.net/all_palaeotemps/ DEjan RaDiVojEVić Geol. an. Balk. poluos., 2020, 81 (2), 87–9896 Fig. 10. The temperature change caused by greenhouse gas accumulation during PETM and technogenic ...

  • Phase relations and physical indicators of municipal waste from old landfills in Serbia

    Dragoslav R Rakić, Irena G Basarić Ikodinović, Jovana M Janković, Tina D Đurić (2021)
    Due to certain similarities of municipal waste and soil, usually for the determination of basic parameters of physical state, laboratory and field tests which are common in geotechnical investigations are used. It is often to construct an apparatus for special purpose to perform some specific laboratory and field tests. Therefore, different values of indicators of municipal waste physical state can be found in the literature. The basic reasons should be found in different definitions and methods that researchers use ...
    municipal waste, moisture content, unit weight, specific gravity, grain size distribution, porosityGeneral Computer Science
    ... depth of taken sample. The first phase means heating at a temperature of 55"% to constant mass. In this stage, loss of mass compared to a constant mass is defined as moisture (W). Thereafter, samples are heated to a temperature of 105%C and again masses of separately analysed fractions ...
    ... temporary storage. It is defined as soil water content by relation of mass lost and remaining material mass, obtained by drying to a constant temperature (usually 55-60C due to the risk of combustion of some materials at higher temperatures). Municipal waste moisture content can be observed based ...
    ... rainfalls and content of organic component is the highest. For the purpose of this paper, water content was determined by drying of material at a temperature of 600C. Since that full waste was taken from two boreholes at Ada Huja landfill and at the same time it was mixed, samples were randomly selected ...

  • Available technological procedures for capturing CO2 in the industrial and power generation sectors

    Lola Tomić, Vesna Karović Maričić, Dušan Danilović, Branko Leković, Miroslav Crnogorac (2021)
    Climate change is a major environmental issue caused by anthropogenic emissions of greenhouse gases. Capturing CO2 and storing it in suitable geological formations is one of the main technological solutions that can provide mitigation of CO2 emission into the atmosphere. Capturing CO2 represents the first phase in process of carbon capture and storage, and includes the application of various technologies for the separation of CO2 produced in the energy and industrial sectors. There are four main systems for capturing ...
    capturing CO2, power plants, CO2 capture systems, CO2 technologies
    ... mainly applied for capturing CO2 in pre-combustion systems [20-21]. CO2 solubility depends on presure and temperature, and it will increase with the increase of pressure and decrease of temperature. This procedure has many applications such as: in natural gas processing, in separation of CO2 from synthesis ...
    ... zirconate and hydrotalcites [4, 23-25]. Based on adsorbent regeneration process, adsorption can be divided into temperature swing adsorption (TSA) where adsorbent is regenerated by rising its temperature; pressure swing adsorption (PSA) and vacuum pressure swing (VPA) where adsorbent is regenerated by reducing ...
    ... by rising its temperature using the Joule effect of passing electricity through a conductor [21, 26-27]. It has been determined that pressure swing adsorption is the best option due to low energy consumption, high regeneration rate, simplicity in application with wide temperature and pressure range ...

  • 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
    ... 573 ◦C confirms the presence of quartz (river sand) and or silicate fume (SiO2) [35]. In this temperature interval (200–600 ◦C) determined mass loss by TG analysis was 3.11%. Weight loss in the third temperature interval (600–800 ◦C) of 2.35% and the endothermic peak at 727 ◦C, is caused by the decomposition ...
    ... pressure) was determined according to EN 13755 and was conducted on the prisms with dimensions 40 mm × 40 mm × 160 mm. Prisms were firstly dried at the temperature of 70 ± 5 ◦C to the constant mass, and then were saturated in water. The percentage difference of masses of a saturated and a dry sample, and the ...
    ... according to standard EN 1015-18 and was conducted on the halves of the prisms having dimensions 40 mm × 40 mm × 160 mm. Prisms were firstly dried at a temperature of 60 ± 5 ◦C to the constant mass (M0). Then the surface of the prism failure was set on the linear supports in a deep vessel, where water was poured ...

  • 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
    ... classified as either high-temperature or low- temperature materials[29]. The primary classes of high-temperature materials include alkali or alkaline-earth oxides such as calcium oxides, alkali silicates and zirconates, as well as double salts, whereas low-temperature adsorbents cover conventional ...
    ... . The high-temperature adsorbents are all chemisorbents, whereas the low-temperature adsorbents are chiefly physisorbents. Characteristics of the adsorbents in addition to the process design influence the efficiency and economics of adsorption processes such as pressure/temperature swing adsorption ...
    ... significant barriers[36]. The gas with CO» is condensed to a temperature between 318 and 323 K, and fed to the absorption column in which the solvent absorbs CO-». The CO-»-rich solution is fed into a heater to increase the temperature of solution, then to a stripper column to release the CO-. The ...

  • Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling

    Branislav Petrović, Veljko Marinović, Zoran Stevanović (2023)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Application of Expansive Mortars for the Formation of Artificial Screens During Blasting in Urban Areas

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Nikola Simić, Jelena Majstorović (2024)
    During construction of buildings in urban areas, sometimes there is a need to blast solid rock mass in the immediate vicinity of the surrounding buildings. In that case, the aim is not only to increase the efficiency of blasting, but also to reduce harmful effects of ground vibration induced by blasting. At the same time, it is very important to protect the buildings located in the safe zone from the blast site as well as remaining rock mass around ...
    expansive mortar, artificial screens, pressure, rock breaking, building foundation

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

    Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić (2023)
    ... sucrose were combined to prepare this nanostructured 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 ...
    ... X-ray diffraction (XRD), FTIR, and Field emission scanning electron microscopy (SEM) were used to characterize the synthesized samples at room temperature. This work was funded by the Ministry of Education, Science and Technological Development of the Republic of Serbia Grant No. 451-03-47/2023-01/ ...

  • Development of a petrographic classification system for organic particles affected by self-heating in coal waste. (An ICCP Classification System, Self-heating Working Group – Commission III)

    M. Misz-Kennan, J. Kus, D. Flores, C. Avila, Z. Büçkün, N. Choudhury, K. Christanis, J.P. Joubert, S. Kalaitzidis, A.I. Karayigit, M. Malecha, M. Marques, P. Martizzi, J.M.K. O'Keefe, W. Pickel, G. Predeanu, S. Pusz, J. Ribeiro, S. Rodrigues, A.K. Singh, I. Suárez-Ruiz, I. Sýkorová, N.J. Wagner, D. Životić (2020)
    Self-heating of coal waste is a major problem in the leading coal-producing and consuming countries, independent of the recent or past coal exploitation history. The phenomenon of self-heating is dependent on many factors such as the properties of organic matter (maceral composition and rank), moisture and pyrite content, climate effects, and storage conditions (shape of the dump or compaction of the coal waste). Once deposited, coal waste undergoes oxidation, which can lead to self- heating with the overall temperatures ...
    Stratigraphy,Economic Geology,Geology,Fuel Technology

  • Fluid inclusion systematics in the Okoška gora polymetallic deposit

    Aleš Šoster, Miloš Velojić, Barbara Potočnik Krajnc, Matej Dolenec (2021)
    ... shaped inclusions, which have larger apour-phase bubbles compared to assemblages 51 апа О1. These features indicate precipitation under higher temperature conditions. In addition, the S2 and Q2 inclusions follow the growth zonesofthe crystals, indicating the simultaneouscrystal growth and fluid nclusion ...
    ... inclusions ofQ1 and S1 occur in linear, subparallel structures and have a higher proportion of liquid phase, ndicating that they formed from a lower temperature flnid and are likely secondary compared o the negative crystal assemblages. The petrographydata for the fluid inclusions suggest the presence of ...
    ... of two mineralizing fluids in the system, raising questions about their origin and metallogenetic fertility. The transition from a higher-temperature to a lower-temperaturč fluid in the system could indicate tWO mineralizing pulses or mixing and dilution of the primary mineralizing fluid by seawater ...

  • Dehydroicetexanes in sediments and crude oils: Possible markers for Cupressoideae

    Hans Peter Nytoft, Geir Kildahl-Andersen, Sofie Lindström, Frode Rise, Achim Bechtel, Danica Mitrović, Nataša Đoković, Dragana Životić, Ksenija A. Stojanović (2019)
    Two previously unidentified dehydroabietane isomers were isolated from Miocene Serbian lignite and Rhaetian (Late Triassic) coaly mudstones from South Sweden and characterized using NMRspectroscopy as cis- and trans-dehydroicetexane. Both have a 9(10?20)-abeo-abietane or icetexane skeleton, consisting of a 6-7-6 tricyclic framework with seven carbons in ring B instead of the usual six in common diterpanes of the abietane-type. Dehydroicetexanes can be detected using GC-MS-MS in m/z 270?146 chromatograms without interference from dehydroabietane or other isomers. Dehydroicetexanes are often abundant ...
    Geochemistry and Petrology

  • Introductory editorial - Special issue: Genesis and protection of groundwater in carbonate aquifer

    Saša Milanović (2019)
    Geochemistry and Petrology

  • Mechanosynthesis and structural characterization of nanocrystalline Ce1–Y O2– (x=0.1–0.35) solid solutions

    Martin Fabián, Bratislav Antić, Vladimír Girman, Milica Vučinić-Vasić, Aleksandar Kremenović, Shigeru Suzuki, Horst Hahn, Vladimír Šepelák (2015)
    A series of nanostructuredfluorite-type Ce1–xYxO2–δ (0rxr0.35) solid solutions, prepared via highenergy milling of the CeO2/Y2O3mixtures, are investigated by XRD, HR-TEM, EDS and Raman spectroscopy. For thefirst time, complementary information on both the long-range and short-range structural features of mechanosynthesized Ce1–xYxO2–δ, obtained by Rietveld analysis of XRD data and Raman spectroscopy, is provided. The lattice parameters of the as-prepared solid solutions decrease with increasing yttrium content. Rietveld refinements of the XRD data reveal increase in microstrains in the host ceria ...
    Ceria, Yttrium, Solid solution, Mechanosynthesis, Oxygen vacancy, Nanocrystalline material

  • Tectonic evolution of the Circum-Moesian orocline of the Carpatho-Balkanides: Paleomagnetic constraints

    Emő Márton, Vesna Cvetkov, Miodrag Banješević, Gábor Imre, Aleksandar Pačevski (2024)
    Apuseni-Banat-Timok-Srednogorie belt, danubicum, paleomagnetism, oroclinal bending

  • Uniaxial compressive strength test before and after standard fire test on rock mass

    Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović (2022)
    ... performed at 24 ± 2 h intervals, is not greater than 0,1% of mass of test sample. After drying, and before testing, samples are stored at room temperature. Load on test specimen must be applied continuously, at a constant pressure increase of 1 ± 0,5 MPa/s. Maximum load must be accurately recorded ...
    ... transmitters type 6321 manufactured by TESTO (Germany), with a range of ± 100 Pa, inside furnace, were used to measure pressure. Inside furnace, temperature was measured in six places with a type K thermocouple. Measuring ranges of type K thermocouples were - 270 ° C to 1372 ° C. Acquisition systems ...
    ... 2018log345 10 ++=Θ tg (1) where: t [min] time, and T [° C] temperature inside furnace depending on time t. In Figure 4 standard fire curve according to SRPS EN 1363-1 is presented. Figure 4. Standard fire ...

  • P-T analiza uglja RB Kolubara

    Rada Vitomir (2024)
    Rudarski basen Kolubara predstavlja jedno od najvažnijih ležišta lignita u Republici Srbiji i ključni je faktor u snabdevanju zemlje energijom. Kvalitet uglja iz ovog basena direktno utiče na efikasnost termoelektrana i zadovoljenje energetskih potreba. U ovom radu, opisan je značaj tehničke i elementarne analiza uglja kako bi se utvrdili fizičko-hemijski parametri uglja iz Rudarskog basena Kolubara. U drugom delu rada dat je opis P-T analize uglja i njen značaj za ocenu mogućnosti čišćenja uglja. Takođe, dati su i rezultati ...
    Rudarski basen Kolubara, pliva tona analiza, lignit, kvalitet uglja, energetska efikasnost
    ... određuje se žarenjem uglja na temperaturi 800 +- 25"C u električnoj mufolnoj peći. Mufolna peć treba da je takve konstrukcije da obezbedi sledeće uslove rada: postizanje temperature za prvih 30 minuta 500%C, za daljih 60 minuta 800 +- 25"%C, mogućnost održavanja ove temperature do kraja izvođenja analize ...
    ... ugljevima za prvih 30 minuta treba dostići temperaturu peći 250%C, za daljih 30 minuta 500*%C ı za poslednjih 60 minuta 800 +- 25"C kod kamenih ugljeva za prvih 60 minuta dostići temperaturu 500%C i za narednih 60 minuta 800 +- 259%C. Krajnju temperaturu žarenja održava 60 minuta, to vreme se smatra ...
    ... ugalj, kameni ugalj i antracit. Lignit predstavlja najmlađi oblik uglja sa najnižom toplotnom vrednošću i najvećim sadržajem vlage, dok je antracit najstariji i najkvalitetniji oblik uglja sa visokom toplotnom vrednošću i niskim sadržajem nečistoća. Karakteristike uglja, kao što su sadržaj vlage, pepela ...

  • Kvantitativna ocena režima i bilansa podzemnih voda u aluvijonu Velike Morave od Bagrdana do ušća u Dunavu

    Aleksandar Balubdžić (2024)
    Aluvijalni sedimenti velikih reka raspolažu značajnim količinama podzemnih voda, što je zajedno sa površinskim vodama dozvolilo razvoj naselja i ljudskih aktivnosti. Ovaj razvoj uslovljava veće potrebe za vodnim resursima i njihovim kvalitetom. Sa povećanjem eksploatacije podzemnih voda, uticaj iste je značajniji i može da dovede do opadanja nivoa podzemnih voda i pogoršanja kvaliteta. Aluvijon Velike Morave ima značajno rasprostranjenje, usled čega predstavlja važno ležište izdanskih voda sa velikim eksploatacionim mogućnostima. Izradom hidrodinamičkog modela aluvijona Velike Morave od Bagrdana do ...
    režim podzemnih voda, bilans podzemnih voda, intergranularna izdan, hidrodinamički model
    ... 0,38 •C ı 21,89 •C. Najviše temperature su u julu mesecu, dok najniže u januaru. U tabeli 2 su prikazane prosečne vrednosti temperature vazduha za period od 1961 - 2022. godine. U tabeli 3 su prikazane srednje, minimalne i maksimalne vrednosti temperatura vazduha registrovane na kišomernoj stanici ...
    ... 0#30-# 4 5 6 7 8 9 IO IL I mp Maksimalna srednja mesečna temperatura (oC) M:sšrcednja mesečna temperatura (oC) m Minimalna srednja mesečna temperatura (oC) Slika 4. Grafički prikaz prosečnih maksimalnih, srednjih i minimalnih mesečnih temperatura za period 1961 - 2022. godine (prema Mladenović, 2023) ...
    ... (prema Mladenović, 2023). 2.2.2. Temperatura vazduha Temperatura vazduha je značajan parametar, usled uticaja na različite procese, kao što su isparavanje i evapotranspiracija, koji čine važne parametre režima podzemnih voda. Srednje vrednosti temperature vazduha u proseku se kreću između 0 ...