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149 items
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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 ...Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović. "Uniaxial compressive strength test before and after standard fire test on rock mass" in Fifth symposium of the Macedonian Association for Geotechnics, Ohrid, North Macedonia, 23-25. 06. 2022, Macedonian Association for Geotechnics (2022)
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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 ...Филип Милетић. Утицај похабаности резних елемената роторног багера на ниво вибрација погона за копање, Београд : [Ф. Милетић], 2023
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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 ...Ђурица Н. Никшић. Флотабилност халкопирита из полиметаличне руде рудника „Рудник”, Београд : [Ђ. Никшић], 2022
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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 zemaljaPredrag Z. Dabić. Sinteza i strukturna karakterizacija novih cezijumskih i kalijumskih silikata sa elementima retkih zemalja, Beograd : P. Dabić, 2022
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Geotehnički aspekti izgradnje visećeg pešačkog mosta u Starom gradu u Užicu
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 ...Zoran Berisavljević, Miloš Marjanović, Uroš Đurić. "Geotehnički aspekti izgradnje visećeg pešačkog mosta u Starom gradu u Užicu" in Zbornik radova / Međunarodno naučno-stručno savetovanje Geotehnički aspekti građevinarstva i zemljotresno inženjerstvo, Vrnjačka banja, 1-3. novembar 2023., Beograd : Savez građevinskih inženjera Srbije (2023.)
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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 analizaMarija D. Prekajski. "Sinteza i karakterizacija nanoprahova u CeO2-Bi2O3 sistemu" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2014-04-04)
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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 ...Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić. "Preparation, synthesis and characterization of nanometric Ca0.9Er0.1MnO3" in Programme and Book of abstracts 15th ECerS Conference for Young Scientists in Ceramics, Novi Sad, Serbia October 11-14, 2023 , Novi Sad : Faculty of Technology, University of Novi Sad (2023)
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Crystal structure of K3EuSi2O7
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 ...Sabina Kovač, Predrag Dabić, Aleksandar Kremenović. "Crystal structure of K3EuSi2O7" in Journal of the Serbian Chemical Society, National Library of Serbia (2021). https://doi.org/10.2298/JSC210218026K
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Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja
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 ...Branko Kostić, Dejan Prelević, Sabina Kovač, Ksenija Eraković, Dragana Životić. "Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
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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 ...Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić. "Synthesis and characterization of nanostructured Ca0.9Er0.1MnO3" in Book of Abstracts Proceedings / 59th Meeting of the Serbian chemical society, Novi Sad, Serbia, June 1-2, 2023, Belgrade : Serbian Chemical Society (2023)
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Утицај обртног магнетног поља на дерацемизацију кристала натријум-хлората
... 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 ...М. Милојевић, А. Жекић, П. Дабић, Б. Вучетић, Б. Максимовић. "Утицај обртног магнетног поља на дерацемизацију кристала натријум-хлората" in XXVII конференција Српског кристалографског друштва, Чачак, 14-15. јун, 2023., Београд : Српско кристалографско друштво (2023)
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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 ...Милена Росић, Маја Милошевић, Мариа Чебела, Владимир Додевски, Весна Лојпур, Марија Васић, Александра Зарубица. "Examination and characterization of nanostructured Co0.9Ho0.1MoO4" in Serbian Ceramic Society Conference - Аdvanced ceramics and application XI New Frontiers in Multifunctional Material Science and Processing Program and the Book of Abstracts, Serbian Academy of Sciences and Arts, Serbia, Belgrade, 18-20. September 2023., Belgrade : Serbian Ceramic Society (2023)
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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 ...Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić. "Investigation of nanostructured Ca0.9Er0.1MnO3 obtained by sucrose nitrate procedure" in Program ; and the Book of abstracts The Eleventh Serbian Ceramic Society Conference »Advanced Ceramics and Application« September 18-20, 2023 Serbian Academy of Sciences and Arts, Belgrade, Serbia , Belgrade : Serbian Academy of Sciences and Art Serbia (2023)
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Mineralogical Discrimination between Authentic and Recent Imitations of Pottery Manufacture in Zlakusa, Serbia
... 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 ...Maja Milošević, Mihovil Logar, Biljana Đorđević. "Mineralogical Discrimination between Authentic and Recent Imitations of Pottery Manufacture in Zlakusa, Serbia" in Nordic Clay Meeting/3rd Symposium Clays & Ceramics 2021, The Latvian Clay Science Society (2021)
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Poreklo asocijacije Ni, Ag i Sn minerala u polimetaličnom ležištu Rudnik
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 ...Stefan Petrović, Aleksandar Pačevski, Viktor Bertrandson Erlandson, Rade Jelenković. "Poreklo asocijacije Ni, Ag i Sn minerala u polimetaličnom ležištu Rudnik" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
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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 ...Sanja J. Armaković, Aleksandra Jovanoski Kostić, Andrijana Bilić, Maria M. Savanović, Nataša Tomić, Aleksandar Kremenović, Maja Šćepanović, Mirjana Grujić-Brojčin, Jovana Ćirković, Stevan Armaković. "Photocatalytic Activity of the V2O5 Catalyst toward Selected Pharmaceuticals and Their Mixture: Influence of the Molecular Structure on the Efficiency of the Process" in Molecules, MDPI AG (2023). https://doi.org/10.3390/molecules28020655
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Determination of Mechanical Properties of Altered Dacite by Laboratory Methods
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 ...... 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 ...Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović. "Determination of Mechanical Properties of Altered Dacite by Laboratory Methods" in Minerals, MDPI AG (2021). https://doi.org/10.3390/min11080813
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Size–strain line-broadening analysis of anatase/brookite (TiO<sub>2</sub>)-based nanocomposites with carbon (C): XRPD and Raman spectroscopic analysis
Aleksandar Kremenović, Mirjana Grujić-Brojčin, Nataša Tomić, Vladimir Lazović, Danica Bajuk-Bogdanović, Jugoslav Krstić, Maja Šćepanović (2022)A size-strain line-broadening analysis of the XRPD patterns and Raman spectra for two anatase/brookite (TiO2)-based nanocomposites with carbon (C) was carried out and the results compared with those of a similar sample free of carbon. The crystal structures and microstructures of anatase and brookite, as well as their relative abundance ratio, have been refined from XRPD data by the Rietveld method (the low amount of carbon is neglected). The XRPD size-strain analysis resulted in reliable structure and microstructure results ...Materials Chemistry, Metals and Alloys, Atomic and Molecular Physics, Optics, Electronic, Optical and Magnetic MaterialsAleksandar Kremenović, Mirjana Grujić-Brojčin, Nataša Tomić, Vladimir Lazović, Danica Bajuk-Bogdanović, Jugoslav Krstić, Maja Šćepanović. "Size–strain line-broadening analysis of anatase/brookite (TiO2)-based nanocomposites with carbon (C): XRPD and Raman spectroscopic analysis" in Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials, International Union of Crystallography (IUCr) (2022). https://doi.org/10.1107/S2052520622001731
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Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)
Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović (2014)Sphene (CaTiSiO5), a calcium titanosilicate ceramic has been prepared from a powder mixture of CaCO3, TiO2 and SiO2 using vibro-milling for homogenization and activation of precursors. During the highpressure and high-temperature synthesis (HPS) process at 4 GPa and 1,200 °C, sphene undergoes into phase transition, from room-temperature phase P21/a to high-temperature phase A2/a. Evidence of that structural phase transition is given in this paper using infrared, Raman spectroscopy and X-ray powder diffraction. Rietveld refinement was employed to get the ...Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović. "Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)" in Physics and Chemistry of Minerals, Springer Science and Business Media LLC (2014). https://doi.org/10.1007/s00269-014-0693-x
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Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering
Josip Išek, Lazar Kaluđerović, Nikola Vuković, Maja Milošević, Ivana Vukašinović, Zorica Tomić (2020)... Materials, 115, 143–52. UNSCEAR (2000) United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and Effects of lonizing Radiation. United Nations Scientific Committee on the Effects of Atomic Radiation, New York, NY, USA, 659 pp. Walawalkar M., Nichol C.K. & Azimi G. (2016) Process ...
... determination, while sample PGIR was subjected only to chem- ical characterization using scanning electron microscopy with energy-dispersive spectrometry (SEM-EDS). Scanning electron microscopy SEM-EDS analysis was performed using a JEOL JSM-11300 SEM coupled with an Oxford Instruments XMax 50 mm ...
... process produces ~5 tons of phosphogypsum for every ton of phosphoric acid manufactured (Hammas eft al., 2013). According to the International Atomic Energy Agency (IAEA), annual phosphogypsum production worldwide is ~160 million tons, of which 50 million tons are produced in China and 40 million ...Josip Išek, Lazar Kaluđerović, Nikola Vuković, Maja Milošević, Ivana Vukašinović, Zorica Tomić. "Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering" in Clay Minerals, Cambridge University press (2020). https://doi.org/10.1180/clm.2020.11