Претрага
950 items
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Synthesis of MnCo2O4 nanoparticles as modifiers for simultaneous determination of Pb(II) and Cd(II)
The porous spinel oxide nanoparticles, MnCo2O4, were synthesized by citrate gel combustion technique. Morphology, crystallinity and Co/Mn content of modified electrode was characterized and determined by Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction pattern analysis (XRD), simultaneous thermogravimetry and differential thermal analysis (TG/DTA). Nanoparticles were used for modification of glassy carbon electrode (GCE) and new sensor was applied for simultaneous determination of Pb(II) and Cd(II) ions in water samples with the ...Vesna Antunović, Marija Ilić, Rada Baošić, Dijana Jelić, Aleksandar Lolić. "Synthesis of MnCo2O4 nanoparticles as modifiers for simultaneous determination of Pb(II) and Cd(II)" in PLOS ONE (2019). https://doi.org/10.1371/journal.pone.0210904
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Long-term planning methodology for improving wood biomass utilization
The insufficiently developed forest management system is often followed by undeveloped forest resources supply chain and insufficient institutional support. These cause inefficient usage of fuel-wood as well as huge amounts of unused forest residues. In order to achieve optimal and long-term sustainable utilisation of biomass, an original methodology based on the interaction of mathematical optimization and backcasting approach has been developed. Mathematical optimization is used for both generation and consideration of techno-economic parameters of the forest biomass supply chain. ...Vladimir Vukašinović, Dušan Gordić, Marija Živković, Davor Koncalović, Dubravka Živković. "Long-term planning methodology for improving wood biomass utilization" in Energy, Elsevier BV (2019). https://doi.org/10.1016/j.energy.2019.03.105
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Automatic construction of a morphological dictionary of multi-word units
The development of a comprehensive morphological dictionary of multi-word units for Serbian is a very demanding task, due to the complexity of Serbian morphology. Manual production of such a dictionary proved to be extremely time-consuming. In this paper we present a procedure that automatically produces dictionary lemmas for a given list of multi-word units. To accomplish this task the procedure relies on data in e-dictionaries of Serbian simple words, which are already well developed. We also offer an evaluation ...electronic dictionary, Serbian, morphology, inflection, multiwordn units, noun phrases, query expansion... of simple words to model these MWUs correctly [4]. When applied to a text in automatic text analysis these FSTs associate recognized MWUs with lemmas as well as with appropriate grammatical categories. Both the associated lem- mas and grammatical categories are in the same format as the one provided by ...
... constituent simple words, it relies completely on FSTs for the inflection of simple words. This way, the generation of all inflected forms with Multiflex is performed with two types of FSTs: for inflection of simple words and for inflection of MWUs. To that end, a lemma for each simple word constituent that ...
... a particular inflectional class, and vice versa, we identified inflectional classes associated with the same additional information. For instance, the class nc nxn2m explained in Table 2 is associated with only one combination of grammatical categories, characterized by the fact that the components differ ...Cvetana Krstev, Ranka Stanković, Ivan Obradović, Duško Vitas, Miloš Utvić. "Automatic construction of a morphological dictionary of multi-word units" in Lecture Notes in Computer Science 6233, Advances in Natural Language Processing, Proceedings of the 7thInternational Conference on NLP, IceTAL 2010, Reykjavik, Iceland, August 2010, Springer (2010): 226-237. https://doi.org/10.1007/978-3-642-14770-8_26
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Integrative GHG Assessment in Oil and Gas Industry
Reducing greenhouse gas emissions is one of the main targets of national strategies in European countries. As a main contributor to emissions, the energy sector is recognized as the most promising to apply measures and actions aimed to decrease GHG emissions. The Oil and Gas industry as a significant contributor to global greenhouse gas emissions is facing a growing need for estimating, mitigating, and reducing the impact of their operations on the atmosphere to stay competitive in a newly ...... provides a comprehensivc representation of thc typical activities and emissions associated with the upstream sector. However, it should be noted that ecven with thesc cfforts, somc flaring is still associated with oil production. By utilizing:this specific dataset, the paper aims to providc valuable ...
... to reduce them to a minimum value. The cnergy sector is in direct correlation with various industries. The O&G industry has a domain role in the energy sector with a space for optimization of production and processing with the aim of reducing GHG emissions. The first prerequisite is developing, the ...
... Gas production and processing (flaring, fugitive emissions, etc.). The model is implemented for a case of a typical upstream oil and gas company, with the aim to identify the main sources of emission. It was shown that the major sourcc of emission is gas flaring, while the kecy contributor is u ...Aleksandar Mirković, Marija Živković, Stevan Đenadić, Darja Lubarda, Chinedu Anyanwa. "Integrative GHG Assessment in Oil and Gas Industry" in Energija, ekonomija, ekologija (2023). https://doi.org/10.46793/EEE23-1.51M
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Mio-Pliocene Geodynamics and its Stratigraphic Consequences in the Area of Avala Mt. (Belgrade, Serbia)
... obtained data were correlated with the results of two earlier drilled wells (KGK-13 and KGK-14) in the Rakovica stream valley (KNEŽEVIĆ, 1989). °e resulting stratigraphic data are interpreted in the context of Neoalpine geodynamics and revealed a complex tectonic structure with pronounced block structures ...
... www.dr.rgf.bg.ac.rs 57 7th International Workshop | Neogene of Central and South-Eastern Europe ysis revealed statistically signiºcant signals with 14.2 m and 2.1–3.3 m wavelength. °ese signals correspond to the 100-kyr eccentricity and precession cycles, respectively. Our results allowed calculation ...
... noticed. °ey lie over the reddish ¼uvial facies of the undivided Lower Miocene. Besides, a lot of new ysis revealed statistically significant signals with 14.2 m and 2.1-3.3 m wavelength. These signals correspond to the 100-kyr eccentricity and precession cycles, respectively. Our results allowed calculation ...Ljupko Rundić, Meri Ganić, Slobodan Knežević, Dejan Radivojević. "Mio-Pliocene Geodynamics and its Stratigraphic Consequences in the Area of Avala Mt. (Belgrade, Serbia)" in 7th International Workshop: Neogene of Central and South-Eastern Europe, Velika, Croatia, maj 2017, Croatian Geological Society (2017)
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Using gravity data to define structural correlation affecting the formation of Neogene basins
A gravity survey can help to define the structural correlation in the study area. The structures that have influenced the development of Neogene basins can be defined using gravity data. By applying mathematical transformations to gravity data, the geological structures (faults, nappes, etc.) that impacted the formation of Neogene basins can be defined. We have taken the part of the Dinarides as the test region. The paper presents the results obtained using the procedure residual, vertical gradient, and total ...Snežana Ignjatović, Ivana Vasiljević, Branisav Sretković, Milanka Negovanović. "Using gravity data to define structural correlation affecting the formation of Neogene basins" in The 54th International October Conference on Mining and Metallurgy, Bor Lake, Serbia, 18-21 October 2023, Bor : University of Belgrade, Technical Faculty in Bor (2023)
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Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia
Dragoljub Bajić, Dušan Polomčić (2014)A groundwater control system was designed to lower the water table and allow the pumping sta-tion “Bezdan 1” to be built. Based on a hydrodynamic analysis that suggested three alternative solutions, mul-ticriteria optimization was applied to select the best alternative. The fuzzy analytic hierarchy process methodwas used, based on triangular fuzzy numbers. An assessment of the various factors that influenced the selec-tion of the best alternative, as well as fuzzy optimization calculations, yielded the “weights” of the alternativesand the ...groundwater lowering, groundwater management scenario, fuzzy analytic hierarchy process,expert knowledge, triangular fuzzy numbers, linguistic variables... a natural way, by linguistic vari- ables, such that fuzzy logic is “computing with words” (ZADEH 1965; ZADEH 1975). As indicated above, the basic unit that represents knowledge in fuzzy logic is a linguistic variable, with its linguistic values that make up fuzzy sets. Combinations of variables and their ...
... “best”. It scored 0.44/1. As a result, Alternative 2 was proposed for the groundwater control system associated with the “Be- zdan 1” PS, whose general and spatial characteristics are: 12 wells with individual capacity of 40 l/s and seven days to lower the water table. In some cases, the FAHP analysis can ...
... fact everyday verbal communica- tion. It is a significant source of uncertainty, because of the transfer of both information and knowledge cou- pled with various uncertainty and imprecision (KOSKO 1993). This is the reason why fuzzy logic systems are distinguished, given that their essence is to handle ...Dragoljub Bajić, Dušan Polomčić. "Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia" in Geološki anali Balkanskoga poluostrva, Belgrade : University of Belgrade - Faculty of mining and geology (2014). https://doi.org/10.2298/GABP1475103B
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Aлтерације перидотита контролисане карактером флуида на примеру харцбургита Рудника - Серпентинизација или талкизација?
Стефан Петровић, Наталија Батоћанин (2020)У раду су приказани резултати испитивања серпентинисаних харцбургита Брђана (43°58'45.1" СГШ, 20°25'12.6" ИГД) и талкизираних харцбургита откривених у интервалу 429-559.8 m у истражној бушотини 330А/18 (44°07'33.2" СГШ, 20°30'28.5" ИГД) на Руднику. Узорци оба локалитета показују карактеристике резидуалних харцбургита из омотача, односно тектонита; лепидобластичне, бластозрнасте, или порфирокластичне структуре и масивне текстуре. Серпентинисани харцбургити и серпентинити Брђана су изграђени од серпентина, ретких реликата оливина и ортопироксена, акцесорног спинела, и веома ретког секундарног магнезита и магнетита. Најдоминантнији састојак (местимично гради и преко ...... mode with CuKα1,2 radiation source (U = 40 kV and I = 30 mA). The low background silicon sample holder was used. The XRPD pattern was collected in 5-75 ° 2θ, with step of 0.01 °, and data collection speed of 5 °/min. The crystal phases were identified in dedicated Rigaku PDXL 2.0 software (with implemented ...
... is connected with the digital camera Leica DC 300 over the program LAS V4.1; - The chemical compositions of mineral phases were identified using a JEOL JSM-6610LV Scanning Electron Microscope that is connected to an X-Max Energy Dispersive Spectrometer. The samples were covered with carbon using ...
... specie (Fig. 5). Relic orthopyroxene grains are very scarce, along with completely replaced pyroxene of preserved crystal forms (Fig. 6). Bent pyroxene suggests on tectonites. Kink banding is best recognized in orthopyroxene with exsolution lamellas of clinopyroxene, diopside/augite (Fig. 7). The ...Стефан Петровић, Наталија Батоћанин. "Aлтерације перидотита контролисане карактером флуида на примеру харцбургита Рудника - Серпентинизација или талкизација?" in Записници српског геолошког друштва, Српско геолошко друштво, Београд (2020)
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Određivanje prostorne distribucije vrednosti hidrauličkih parametara izdani: primer površinskog kopa „Radljevo“
Najčešće se kalibracija hidrodinamičkih modela vršila manuelno - „probanjem“ sa različitim vrednostima hidrauličkih parametara i hidrauličkih karakteristika graničnih uslova. Ovakav način rada zahteva veliko znanje i iskustvo eksperta, pri čemu ostaje otvoreno pitanje da li dobijeno rešenje ima optimalan skup parametara. Primenom optimizacione metode, koja se zasniva na Gauss-Marquardt-Levenberg-ovom algoritmu, i PEST softvera, ...Dragoljub Bajić, Dušan Polomčić, Jelena Ratković, Predrag Pajić. "Određivanje prostorne distribucije vrednosti hidrauličkih parametara izdani: primer površinskog kopa „Radljevo“" in 9. Međunarodni simpozijum o upravljanju podzemnim resursima, Zaječar 2019., Megatrend Univerzitet, Fakultet za menadžment, Zaječar (2019)
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Ecological status of the Lim river alluvium in Serbia
Amel Kurbegović, Boris Vakanjac, Vesna Ristić Vakanjac, Mirjana Bartula, Zorana Naunović, Nikola Milovanović, Jovan Kovačević (2022)Three countries share the catchment of the Lim River and they have been engaged in an eco-logical struggle for years, to conserve the river, its tributaries, and biodiversity. Honoring international conventions and declarations, along with active involvement of the civil society and support of Eu-ropean Union agencies, major efforts are being made to draw attention to the degradation of nature, especially water, which is essential for life on the planet Earth. Considering that natural resources are limited and that ...Amel Kurbegović, Boris Vakanjac, Vesna Ristić Vakanjac, Mirjana Bartula, Zorana Naunović, Nikola Milovanović, Jovan Kovačević. "Ecological status of the Lim river alluvium in Serbia" in Fresenius Environmental Bulletin, Parlar Scientific Publications (2022)
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Epidotized sanidine in quartzlatites from Grot
Propilitska alteracija je veoma česta u gornjokredno-tercijarnim vulkanitima Srbije. Kvarclatiti Grota, otkriveni na dubini od oko 550 m u jednoj od istražnih bušotina su holokristalaste porfirske strukture sa fenokristalima sanidina dimenzija i do 1,5 x 2 cm. Optičkim ispitivanjima su u kvarclatitu potvrdjeni i elementi sitaste, pojkilitske i glomeroporfirske strukture. Kao fenokristali prisutni su sanidin, plagioklas, kvarc, biotit i amfiboli. Sekundarni minerali su hlorit, epidot, coisit, Fe-hidroksidi, redak kalcit i ilit. U fenokristalima sanidina se zapažaju „lepeze“ izduženih kristala ...Danica Srećković-Batoćanin, Suzana Erić, Nikola Novičić, Nikola Pašajlić, Natalija Batoćanin. "Epidotized sanidine in quartzlatites from Grot" in Book of Abstracts, III Congress of Geologists of Bosnia and Herzegovina with international participation, Neum, 21. – 23.09.2023, Ilidža : Udruženje/udruga geologa u Bosni i Hercegovini (2023)
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VENTEX: An Expert System for Mine Ventilation Systems Analysis
Analiza sistema za ventilaciju je komleksan proces, koji bazira na proračunu brojnih parametara, koji se odnose na: stanje mreže, provetrenost, stabilnost sistema, gubitke vazduha, klimatske uslove, gasno stanje, ugroženost od požara i opasne prašine. Navedeni problemi se uspešno rešavaju paketom SimVent, ali potpuno razumevanje i korišćenje dobijenih rezultata zahteva angažovanje iskusnog specijaliste iz oblasti ventilacije. Rešenje je nađeno u kreiranju ekspertnog sistema VENTEX, čija je baza znanja formalizacija ekspertskog znanja iz oblasti ventilacije rudnika. U radu je prikazana metodologija ...... of the working process in mines with underground exploitation. Contemporary mining theory already operates with a number of mathematical methods which can be used to solve mine ventilation problems. These methods are used in current engineering practice with the help of appropriate software ...
... conditions, gas state, fire risk and dangerous dust pollution risk. The solution of these problems relies to a great extent on numerical methods. With the development of computer technology these methods were incorporated as numerical routines in software packages, such as the mine ventilation ...
... developed at the Faculty of Mining and Geology of the University of Belgrade. VENTEX was developed by upgrading the existing numerical package SimVent with declarative knowledge representing the rules and heuristics mine ventilation experts use in solving the problem at hand. Section 2 of this paper ...Ranka Stanković, Nikola Lilić, Ivan Obradović. "VENTEX: An Expert System for Mine Ventilation Systems Analysis" in YU Info '96 Brezovica, Društvo za informacione sisteme i računarske mreže (1996)
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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
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, ANFISMiljan Gomilanović, Miloš Tanasijević, Saša Stepanović, Filip Miletić. "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" in Energies, MDPI AG (2023). https://doi.org/10.3390/en16072958
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Application of VIКOR method in the selection of an optimal splution of excavation “Borska Reka” ore deposit
Sanja Bajić, Dragoljub Bajić, Branko Glušćević, Radmila Gaćina. "Application of VIКOR method in the selection of an optimal splution of excavation “Borska Reka” ore deposit" in 9th International Conference Mining and Environmental protection MEP, 24 – 27 May 2023, Sokobanja, Serbia , Belgrade : University of Belgrade-Faculty of mining and geology (2023)
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History of meteorite donations to the Collection of Minerals and Rocks of the University of Belgrade, Faculty of Mining and Geology (Serbia)
... further developments of meteorite collections and increased the potential for sample exchanges with foreign museums. Prof. Josif Pančić was a very active and respected scientist across Europe, and with his collaborations and private efforts, he collected 95 well-known meteorites worldwide. Unfortunately ...
... accompanied with a catalogue. A revision of the collection was, therefore, not directly based on the original samples’ description but rather on facts announced at the Meeting of the Serbian Geological Society, which was held in 1899. It was confirmed that the samples and labels with French handwriting ...
... there are four additional meteorite specimens in the Collection of Minerals and Rocks. Among them, there are the sample named Mocs with handwritten etiquette with all necessary descriptions (Meteorite, Lithite, Chantonite, fall 3.02.1972., Mocs, Cluj, Romania, weigh 24.55, No 32), two iron meteorite ...Alena Zdravković, Maja Milošević, Kristina Šarić, Ivana Jelić, Ana Černok. "History of meteorite donations to the Collection of Minerals and Rocks of the University of Belgrade, Faculty of Mining and Geology (Serbia)" in 9th International Conference Mineralogy and Museums, Sofia, Bulgaria, Earth and Man National Museum and Bulgarian Mineralogical Society (2021)
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Geothermal potential, chemical characteristic and utilization of groundwater in Serbia
To collect and unify data about all geothermal resources in Serbia, a database was formed. The database allows us to perceive the geothermal resources of Serbia and their potential for utilization. Based on the data available in the geothermal database, the estimated temperatures of reservoirs, heat power, and geothermal energy utilization were calculated. The database contains 293 geothermal records (springs, boreholes) registered at 160 locations, with groundwater temperatures in the range between 20 and 111 °C. The maximum expected ...Geothermal database, Geothermal resources, Geothermal potential, Hydrochemistry, Hierarchical cluster analysis, SerbiaTanja Petrović Pantić, Katarina Atanasković Samolov, Jana Štrbački, Milan Tomić. "Geothermal potential, chemical characteristic and utilization of groundwater in Serbia" in Environmental Earth Sciences, Springer Link (2021). https://doi.org/https://doi.org/10.1007/s12665-021-09985-w
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The role of non-covalent intermolecular interactions on the diversity of crystal packing in supramolecular dihalopyridine–silver(i) nitrate complexes
Sunčica Roca, Lucija Hok, Robert Vianello, Mladen Borovina, Marijana Đaković, Ljiljana Karanović, Dražen Vikić-Topić, Zora Popović (2020)Six novel 1 : 2 complexes of silver(I) nitrate with 2,5-, 2,6- and 3,5-dihalopyridines (halo stands for chlorine and bromine) were prepared by the reaction of an aqueous solution of AgNO3 and the corresponding pyridine derivative in a water–alcohol solution. In spite of having analogous empirical formulae, they reveal intriguing structural differences, except [Ag(NO3)(2,5-Cl2py)2]n (1) and [Ag(NO3)(2,5-Br2py)2]n (4), which are isostructural. In contrast, [Ag(NO3)(3,5-Cl2py)2]2 (3) is dimeric, while its Br analogue [Ag(NO3)(3,5-Br2py)2]n (6) is polymeric in nature, being the ...Sunčica Roca, Lucija Hok, Robert Vianello, Mladen Borovina, Marijana Đaković, Ljiljana Karanović, Dražen Vikić-Topić, Zora Popović. "The role of non-covalent intermolecular interactions on the diversity of crystal packing in supramolecular dihalopyridine–silver(i) nitrate complexes" in CrystEngComm, Royal Society of Chemistry (RSC) (2020). https://doi.org/10.1039/D0CE01257B
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Steel Arch Support Deformations Forecast Model Based on Grey–Stochastic Simulation and Autoregressive Process
Relatively large deformations of the steel arch support in underground coal mines in the Republic of Serbia present one of the main problems for achieving the planned production of coal. Monitoring of the critical sections of the steel arch support in the underground roadways is necessary to gather quality data for the development of a forecasting model. With a new generation of 3D laser scanners that can be used in potentially explosive environments (ATEX), deformation monitoring is facilitated, while ...čelična podgrada, prognoza deformacija, vremenske serije, grey-stohastička simulacija, autoregresija, podzemni rudnik ugljaLuka Crnogorac, Suzana Lutovac, Rade Tokalić, Miloš Gligorić, Zoran Gligorić. "Steel Arch Support Deformations Forecast Model Based on Grey–Stochastic Simulation and Autoregressive Process" in Applied Sciences, MDPI AG (2023). https://doi.org/10.3390/app13074559
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Hydrodynamic analysis of radial collector well ageing at Belgrade well field
The origin and effect of hydraulic resistances on the rate of ageing of radial collector wells are identified through numerical hydrodynamic analysis. The research includes hydrodynamic modeling of one such well with new laterals at Belgrade well field. The performance of the laterals is aggravated by rapid ageing. The change in the hydraulic parameters of the laterals during the first decade of operation is analyzed through simulations of the groundwater regime with realistically specified geometries and hydraulics of the ...Đorđije Božović, Dušan Polomčić, Dragoljub Bajić, Jelena Ratković. "Hydrodynamic analysis of radial collector well ageing at Belgrade well field" in Journal of Hydrology, Elsevier BV (2019). https://doi.org/10.1016/j.jhydrol.2019.124463
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Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution
Vesna Pavelkić, Tanja Brdarić, Marija Petrović, Gavrilo Šekularac, Milica Košević, Lato Pezo, Marija Ilić (2015)The applicability of Peleg model was investigated for predicting mass transfer kinetics during the osmotic dehydration (OD) process of pears, at different concentrations (40, 60 and 70%, w/w) and temperatures (20, 35 and 50 °C) of sucrose solution. Increase in sucrose solution concentration resulted in higher water loss (WL) and solid gain (SG) values through the osmotic treatment period. After 360 min of osmotic treatment of pears, WL ranged from 23.71 to 31.68% at 20 °C, from 24.80 to ...Vesna Pavelkić, Tanja Brdarić, Marija Petrović, Gavrilo Šekularac, Milica Košević, Lato Pezo, Marija Ilić. "Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution" in Chemical Industry and Chemical Engineering Quarterly (2015). https://doi.org/10.2298/CICEQ141014004P