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Упит dcterms_subject_txt:Atomic force microscopy

157 items

  • Geostatički proračuni sanacije klizišta šipovima

    Slobodan Ćorić, Dragoslav Rakić, Dušan Berisavljević (2019)
    U ovom radu su, polazeći od rezultata geotehničkih istraživanja, prikazani geostatički proračuni sanacije klizišta vertikalnim šipovima. Metodologija proračuna je složena, jer podrazumeva interakciju klizišta i stabilizirajućih šipova. Stoga se simultano analiziraju stabilnost klizišta i stabilnost šipova. Prilikom određivanja bočne otpornosti tla oko šipova koristi se metoda Brinč Hansena koja uzima u obzir trodimenzionalne uslove u tlu i može da se primeni u složenim geološkim uslovima koji su česti u Srbiji. Analize stabilnosti klizišta vrše se odgovarajućim metodama granične ravnoteže. ...
    sanacija klizišta, interakcija klizišta i šipa, bočna otpornost šipova, stabilnost klizišta i šipova
    ... mogu da se provere vrednosti dobijene povratnom analizom. SIGURNOSTI KLIZIŠTA s zahtevani faktor sigurnosti Fs (Slika 5). Figure 5. Stabilizing force s = 1.2 – 1.5, zemljotresa Fs = 1.1. horizontalne sile Hp šip u kliznom telu (Slika 6). Figure 6. Calculation of pile stability 298 1 2 pF - ...
    ... to geological conditions and types of slope movement, Bulletin IAEG., No. 16, 1977, pp..131-155. Ito, T., Matsui, T., Methods to estimate lateral force acting on stabilizing piles, Soil and Foundation, Vol. 15, No. 4, 1975., pp. 43-59. -18, Tuzla, 2000. NAVFAC, Design Manual DM -7.1., Soil mechanics ...

  • 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

  • An update on the mineral-like Sr-containing transition metal arsenates

    Tamara Đorđević, Ljiljana Karanović (2021)
    We report on the crystal structures of three novel synthetic SrM-arsenates (M = Ni and Fe3+), isostructural or structurally related to the minerals from tsumcorite, carminite and brackebuschite groups. They were synthesised under mild hydrothermal conditions and further characterised using single-crystal X-ray diffraction (SXRD), scanning electron microscopy with energy dispersive spectroscopy (SEMEDS) and Raman spectroscopy. SXRD and SEM-EDS yielded formulae: (I) SrNi2(AsO4)2·2H2O, (II) Sr1.4Fe3+ 1.6(AsO4)2(OH)1.6 and (III) SrFe3+(AsO4)(AsO3OH). All three structures are built up of slightly distorted MO6 octahedra ...
    арсенати метала, кристална структура, дифракција рендгенских зрака на монокристалима, хидротермална синтеза, Раманова спектроскопија, релевантна једињења у животној средини, арсенeochemistry and Petrology

  • 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)
    ... results are shown in Table 1. Table 1. Uniaxial Compressive Strength Sample Sample Mass [gr] Dimensions [cm] Base Area [cm2] Force [kN] Uniaxial Compressive Strength [MPa] 1 889,25 6,98x6,99x6,89 48,79 390 80 2 856,58 6,85x6,87x6,98 47,06 184 39 3 886,40 6,96x6,92x6 ...
    ... strength of samples (7-12) after standard fire test was not possible because samples cracked so much that they disintegrated even before application of force on the hydraulic press. In Figure 5 samples after standard fire test are shown. Figure 5. Samples prepared according to SRPS EN 1926 after ...

  • Утицај похабаности резних елемената роторног багера на ниво вибрација погона за копање

    Филип Милетић (2023)
    У докторској дисертацији је анализиран утицај похабаности резних елемената роторног багера на потрошњу електричне енергије и ниво амплитуде вибрација погона за копање. Креиран је модел који у функцији стања резних елемената дефинише зависност разматраних физичких феномена. За развој модела примењене су једначине теорије осцилација и Ватметарска метода [1] којом се одређује потрошња електричне енергије. За верификацију модела извршена су мерења на роторном багеру SRs2000.32/5+VR ангажованом на откопавању откривке на површинском копу Тамнава–Западно поље. Обављено је пет мерења. Резни елементи су ...
    роторни багер, резни елементи, хабање, вибрације, потрошња електричне енергије

  • Geotehnički aspekti izgradnje visećeg pešačkog mosta u Starom gradu u Užicu

    Zoran Berisavljević, Miloš Marjanović, Uroš Đurić (2023.)
    U radu su prikazani rezultati geotehničkih istraživanja za potrebe izgradnje visećeg pešačkog mosta preko klisure reke Đetinje u Užicu. Predviđeno je da most, sistema prednapregnute trake, omogući prelaz pešacima sa desne dolinske strane na stranu Starog grada, koja je opasana strmom liticom (cca. 40 m visine). Za potrebe formiranja geotehničkog modela i strukturnog sklopa krečnjačke stenske mase korišćen je postupak fotogrametrijskog snimanja dronom. Predviđeno je da se zatežuća sila (od oko 30 MN), koju most prenosi na obalni stub, ...
    fotogrametrija, stabilnost kosina, pukotine, prednapregnuta sidra, test granične nosivosti, paker (Ližonov) test
    ... town is located. Geotechnical model of the limestone rock mass and joint network model are formed by utilization of drone photogrammetry. The tensile force (approx. 30 MN) induced on the bridge pillar should be accepted and transfered to the rock mass by the system of prestressed anchors. Two investigation ...

  • Флотабилност халкопирита из полиметаличне руде рудника „Рудник”

    Ђурица Н. Никшић (2022)
    The doctoral dissertation Chalcopyrite flotability from polymetallic "Rudnik" mine ore consists of two parts. The first part is a general part in which the theoretical foundations of the flotation concentration process, the flotation properties of chalcopyrite, the influence of certain flotation reagents and the mechanism of action on the flotation properties of chalcopyrite are presented. This part also describes the process of flotation concentration of polymetallic ore from the "Rudnik" mine. The second part is ...
    Халкопирит, флотацијска концентрација, KAX, NaCN, pH пулпе

  • Sinteza i strukturna karakterizacija novih cezijumskih i kalijumskih silikata sa elementima retkih zemalja

    Predrag Z. Dabić (2022)
    Predmet i ciljevi naučnog istraživanja ove doktorske disertacije su sinteza i strukturna karakterizacija novih cezijumskih i kalijumskih silikata sa elementima retkih zemalja. Istraživanja su izvedena u okviru sistema SiO2–REE2O3–XF, gde REE predstavlja trovalentni katjon elementa retkih zemalja (Sc, Y, Sm, Eu, Gd, Ho, Er, Tm, Yb, Lu), dok X predstavlja jednovalentni katjon alkalnih metala (K, Cs). Rad na disertaciji bio je fokusiran na sintezu monokristala, određivanje kristalnih struktura, kao i na kristalografsko i kristalohemijsko ispitivanje sintetisanih monokristala. Monokristali su sintetisani ...
    alkalni silikati elemenata retkih zemalja, kristalna struktura, sinteza metodom fluksa, rendgenska difrakcija na monokristalu, elementi retkih zemalja

  • Sinteza i karakterizacija nanoprahova u CeO2-Bi2O3 sistemu

    Marija D. Prekajski (2014-04-04)
    Nanoprahovi kristalnih faza iz serije čvrstih rastvora u pseudo-binarnom sistemuCeO2-Bi2O3 sintetisani su primenom jednostavne i ekonomične samopropagirajućemetode na sobnoj temperaturi korišćenjem nitrata metala i natrijum-hidroksida kaopolaznih supstanci. Osim krajnjih članova niza, CeO2 i niskotemperaturne polimorfnemodifikacije α-Bi2O3, sintetisani su i čvrsti rastvori nominalnog sastava Ce1-xBixO2-δ,gde je x = 0,1; 0,2; 0,3; 0,4; 0,5; 0,6; 0,7; 0,8; 0,9. Rezultati proučavanja metodomrendgenske difraktometrije na polikristalnom materijalu i ramanske spektroskopskeanalize pokazali su da su sintetisani prahovi sa nižim sadržajem bizmuta (x = 0,1 ...
    nanostrukturni materijali, čvrsti rastvori, CeO2, Bi2O3, rendgenskadifraktometrija praha, Ritveldova metoda, mikrostrukrurna analiza

  • Crystal structure of K3EuSi2O7

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović (2021)
    alkalni silikati elemenata retkih zemalja, kristalna struktura, sinteza metodom fluksa, rendgenska difrakcija na monokristalu
    ... applied during the data reduction. The structure of K3EuSi2O7 crystallizes in space group P63/mcm. Since it is isostructural with K3ErSi2O7,15 atomic coordinates of this structural analogue were used as a starting model for structure refinement. When Er3+ was replaced with Eu3+ the model converged ...
    ... with a step size of 0.02° and time per step of 1.25 s. PDXL 2 software18 was used for the powder diffraction data analysis. Scanning electron microscopy (SEM) was used for the morphological characteriza- tion. The analyses were carried out on a single crystal using a JEOL JSM-6610LV instrument ...
    ... pattern represents overlaid positions of Bragg’s peaks calculated from K3EuSi2O7 CIF. OnLin e Fir st 8 KOVAČ et al. Scanning electron microscopy (SEM) The crystal morphology of a single K3EuSi2O7 crystal obtained using a SEM is shown in Fig. 5. Elongated prismatic crystal is clearly visible ...

  • Preparation, synthesis and characterization of nanometric Ca0.9Er0.1MnO3

    Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić (2023)
    ... (differential thermal analysis (DTA), X-ray diffraction (KRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning eclectron microscopy (FESEM), and inductively coupled plasma (ICP)). 65 ...

  • Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja

    Branko Kostić, Dejan Prelević, Sabina Kovač, Ksenija Eraković, Dragana Životić (2022)
    Ugljevi niskog ranga – ligniti u Republici Srbiji predstavljaju glavnu energetsku sirovinu koja se koristi za proizvodnju električne energije. Rudarstvo u Srbiji doprinosi bruto dodatoj vrednosti sa 1,8% (2020; https://publikacije.stat.gov.rs/). Sagorevanjem ugljeva niskog ranga u termoelektranama generišu se velike količine elektrofilterskog pepela i pepela, koje često predstavljaju jedan od izvora zagađenja životne sredine usled sadržaja toksičnih elemenata. Dalja upotreba produkata sagorevanja zavisi od njihovog sastava i sadržaja toksičnih mikroelemenata. Svakodnevno sagorevanje lignita u termoelektranama uslovljava konstantan monitoring potencijalno toksičnih ...
    ugalj, produkti sagorevanja, XRF, ICP-MS

  • Photocatalytic Activity of the V2O5 Catalyst toward Selected Pharmaceuticals and Their Mixture: Influence of the Molecular Structure on the Efficiency of the Process

    Sanja J. Armaković, Aleksandra Jovanoski Kostić, Andrijana Bilić, Maria M. Savanović, Nataša Tomić, Aleksandar Kremenović, Maja Šćepanović, Mirjana Grujić-Brojčin, Jovana Ćirković, Stevan Armaković (2023)
    Due to the inability of conventional wastewater treatment procedures to remove organic pharmaceutical pollutants, active pharmaceutical components remain in wastewater and even reach tap water. In terms of pharmaceutical pollutants, the scientific community focuses on -blockers due to their extensive (over)usage and moderately high solubility. In this study, the photocatalytic activity of V2O5 was investigated through the degradation of nadolol (NAD), pindolol (PIN), metoprolol (MET), and their mixture under ultraviolet (UV) irradiation in water. For the preparation of V2O5, facile ...
    DFT analysis, metoprolol, nadolol, nanomaterial characterization, photocatalysis, pindolol, β-blocker
    ... analysis indicates that the main elements of the catalyst are vanadium and oxygen, and no other impurity elements could be detected (Figure 4). The atomic percentage of V and O in Spectrum 1 is estimated as 39.86% and 60.14%, respectively, indicating, possible oxygen deficiency on the edge of the ...
    ... 154104. [CrossRef] [PubMed] Caldeweyher, E.; Ehlert, S.; Hansen, A.; Neugebauer, H.; Spicher, S.; Bannwarth, C.; Grimme, S. A generally applicable atomic- charge dependent London dispersion correction. J. Chem. Phys. 2019, 150, 154122. [CrossRef] [PubMed] Grimme, S.; Ehrlich, S.; Goerigk, L. Effect ...
    ... Devlin, E;.; Chabalowski, C.; Frisch, M. Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using, Density Functional Force Fields. J. Phys. Chem. 1994, 98, 11623—11627. [CrossRef] 'Vosko, S.H.; Wilk, L.; Nusair, M. Accurate spin-dependent electron liquid correlation energjes ...

  • Determination of Mechanical Properties of Altered Dacite by Laboratory Methods

    Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović (2021)
    This paper presents a methodology for determining the uniaxial and triaxial compressive strength of heterogeneous material composed of dacite (D) and altered dacite (AD). A zone of gradual transition from altered dacite to dacite was observed in the rock mass. The mechanical properties of the rock material in that zone were determined by laboratory tests of composite samples that consisted of rock material discs. However, the functional dependence on the strength parameter alteration of the rock material (UCS, intact ...
    Geology, Geotechnical Engineering, Engineering Geology
    ... compression testing frame with sufficient pressure capacity and capable of applying a force perpendicular to the specimen base. UCS is calculated according to the following equation: σci UCS = P/A (1) where: P—maximum force at the moment of failure, A—specimen’s cross-section area. Triaxial tests were carried ...
    ... Åkesson, U.; Stigh, J.; Lindqvist, J.E.; Göransson, M. The influence of foliation on the fragility of granitic rocks, image analysis and quantitative microscopy. Eng. Geol. 2003, 68, 275–288. [CrossRef] 15. Räisänen, M. Relationships between texture and mechanical properties of hybrid rocks from the Jaala–Iitti ...

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

    Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić (2023)
    ... parameters, structural changes, and specific surface area were investigated. DTA, 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 T ...

  • Утицај обртног магнетног поља на дерацемизацију кристала натријум-хлората

    М. Милојевић, А. Жекић, П. Дабић, Б. Вучетић, Б. Максимовић (2023)
    ... 200- 1200 rpm with a step of 200 rpm. After the growth, which lasted about 4 h, the orientation of the crystals was determined by polarization microscopy. The results show that the rotational frequency of the field affects the fraction of the obtained crystals. At frequencies of 800, and 1200 rpm ...

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

    Милена Росић, Маја Милошевић, Мариа Чебела, Владимир Додевски, Весна Лојпур, Марија Васић, Александра Зарубица (2023)
    ... Crystallography, Petrology and Geochemistry, Faculty of Mining and Geology, University of Belgrade, Đušina 7, 11000 Belgrade, Serbia ŠDepartment of Atomic Physics, Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, University of Belgrade, P.O. Box 522, 11001 Belgrade ...
    ... samples were examined by DTA, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra, Spectroscopy, Field emission scanning electron microscopy (FESEM), and nitrogen adsorption method. The acquired nanopowder showed a tendency for agglomeration, inhomogeneous microstructure, and plate-like ...

  • 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)
    ... 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 used to characterize the obtained powder. P24 Experimental and numerical determination of the ...

  • Mineralogical Discrimination between Authentic and Recent Imitations of Pottery Manufacture in Zlakusa, Serbia

    Maja Milošević, Mihovil Logar, Biljana Đorđević (2021)
    ... the characteristic attributes for a specific technique. Phase and mineral composition, texture, and structure of the samples were analysed by microscopy of cross-section preparations perpendicular to the vessel walls (Leitz polarization microscope). The numerical colour specification was calculated ...

  • Poreklo asocijacije Ni, Ag i Sn minerala u polimetaličnom ležištu Rudnik

    Stefan Petrović, Aleksandar Pačevski, Viktor Bertrandson Erlandson, Rade Jelenković (2022)
    Rudnomikroskopska, SEM-EDS i LA-ICP-MS ispitivanja rudne mineralizacije iz Pb-Zn-Cu-(Ag) ležišta Rudnik, ukazala su na lokalno prisustvo specifične asocijacije minerala nikla, srebra i kalaja, deponovane u tektonskoj breči, arsenopiritsko-pirotinskim, piritsko-pirotinsko-arsenopiritskim i kvarcno-sulfidnim žicama u harcburgitima. U tektonskoj breči deponovan je polimineralni sulfidni agregat kojeg čine pirotin (50), galenit, sfalerit i halkopirit. Arsenopiritsko-pirotinske žice odlikuje dezintegrisani agregat arsenopirita cementovan sa pirotinom. U piritsko-pirotinsko-arsenopiritskim žicama masivni pirit (50%) prorasta sa arsenopiritom i cementovan je polimineralnim agregatom pirotina, galenita i sfalerita. Minerali nikla, srebra ...
    Rudnik, ferokesterit, argentopentlandit, harcburgit, rudne žice