Supplementary data for the article: Sakan, S.; Popović, A.; Škrivanj, S.; Sakan, N.; Đorđević, D. Comparison of Single Extraction Procedures and the Application of an Index for the Assessment of Heavy Metal Bioavailability in River Sediments. Environmental Science and Pollution Research 2016, 23 (21), 21485–21500. https://doi.org/10.1007/s11356-016-7341-6

Supplementary material for: [https://doi.org/10.1007/s11356-016-7341-6]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2347

Supplementary data for article: Sakan, S.; Dević, G.; Relić, D.; Anđelković, I.; Sakan, N.; Đorđević, D. Risk Assessment of Trace Element Contamination in River Sediments in Serbia Using Pollution Indices and Statistical Methods: A Pilot Study. Environmental Earth Sciences 2015, 73 (10), 6625–6638. https://doi.org/10.1007/s12665-014-3886-1

Supplementary material for: [https://doi.org/10.1007/s12665-014-3886-1]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1701

Geochemical Fractionation and Assessment of Probabilistic Ecological Risk of Potential Toxic Elements in Sediments Using Monte Carlo Simulations

The need for further research into potentially toxic elements in Serbian rivers led to an investigation of distributions, sources, and ecological risks in a sample base of sediments from 15 rivers. The analyses were carried out through both experimental and theoretical methods. Geochemical fractionation of Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, As, V, and Zn in sediments was studied using a sequential extraction procedure. Both a Håkanson risk index (RI) and a Monte Carlo simulation (MCS) were used in order to estimate ecological risk, applying the probability distribution of RI values instead of single-point calculations. In order to both further the development of the used method and include additional processes, software for the simulations was developed instead of using proprietary solutions. Metal fractionation showed high percentage recoveries of Cd, Cr, Co, Cu, Fe, Ni, and V in residual fractions. The high content of Pb, Mn, and Zn in mobile fractions might cause serious environmental concerns. In some localities, Cu and Cd could be problematic elements, since their mobility was high. An environmental assessment based on the described criteria provided risk levels varying from low to median (mainly contributed by Cd and Cu)

Supplementary data for the article: Sakan, S.; Popović, A.; Škrivanj, S.; Sakan, N.; Đorđević, D. Comparison of Single Extraction Procedures and the Application of an Index for the Assessment of Heavy Metal Bioavailability in River Sediments. Environmental Science and Pollution Research 2016, 23 (21), 21485–21500. https://doi.org/10.1007/s11356-016-7341-6

Supplementary material for: [https://doi.org/10.1007/s11356-016-7341-6]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2347

Supplementary data for article: Sakan, S.; Dević, G.; Relić, D.; Anđelković, I.; Sakan, N.; Đorđević, D. Risk Assessment of Trace Element Contamination in River Sediments in Serbia Using Pollution Indices and Statistical Methods: A Pilot Study. Environmental Earth Sciences 2015, 73 (10), 6625–6638. https://doi.org/10.1007/s12665-014-3886-1

Supplementary material for: [https://doi.org/10.1007/s12665-014-3886-1]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1701

Supplementary data for the article: Sakan, S.; Frančišković-Bilinski, S.; Đorđević, D.; Popović, A.; Sakan, N.; Škrivanj, S.; Bilinski, H. Evaluation of Element Mobility in River Sediment Using Different Single Extraction Procedures and Assessment of Probabilistic Ecological Risk. Water 2021, 13 (10), 1411. https://doi.org/10.3390/w13101411.

Supplementary material for: [ https://doi.org/10.3390/w13101411]Related to published version: [https://cherry.chem.bg.ac.rs/handle/123456789/4546

Software/hardware design of decision-making controllers for object navigation in horizontal plane

Cilj rada je istražiti mogućnosti orijentacije objekta u horizontalnoj ravnini, počevši od njegovog početnog kursa u zahtjevani rakurs, koristeći pojednostavljene metode navigacije. Usmjeravanje gibanja objekta koristi kontrolirane pogonske impulse neravnomjerno distribuirane u ograničenom vremenskom intervalu gibanja. Dizajnirane su tri metode logičkog odlučivanja za izračunavanje najbolje putanje, čije su greške na cilju minimalne. Računanje pogonskih impulsa, njihovih izvršnih instanci kao i tipova, prezentirani su u ovom radu. Razvijene kontrolne mjere su: modificirana višestruka shooting metoda, odnosno novi zakon upravljanja kako je nazvan u ovom radu, trenutna orijentacijska greška, kao i metoda fuzzy logike. Metode su projektirane kao softver za donošenje odluke implementiran u elektronski hardver kao predefinirani programabilni kontroler. To daje preliminarno programiranje usmjeravanja objekta na samom početku kursa gibanja prema ciljnoj točki smještenoj van početnog pravca. Metodama se optimiziraju raspodijele ukupno determiniranog vremena radi realiziranja odgovarajućih tipova i broja pogonskih impulsa u sekvencama. Simulacijski testovi ovih metoda, kao i projektirani hardver, također su prezentirani u radu kao doprinos razvojnom istraživanju upravljanja horizontalnim gibanjem.The paper aims to research the orientation possibilities of an object in the horizontal plane, from its start course into a required orientating recourse, by using simplified navigation methods. The object’s directed motion uses controlling powering impulses, variable distributed in time, during constrained motion time. Three logical decision-making methods are designed for calculating the best maneuvering trajectory with minimal error on the target. Computing the powering impulses, their execution instances, as well as their types, are ensured by the methods and presented in the paper. The developed controlling methods are: a modified multiple shooting method, a new control law, called in this paper, current error orientation, as well as a fuzzy logic method. These methods are designed as decision-making software implemented in an electronic hardware as a predefined programmable controller. This provides pre-programmable orientation of the object at the very beginning of course motion, towards a targeted point settled out of initial direction. The controlling methods use optimal diversification of full elapsed determining time to execute, in sequences, appropriate types and number of powering impulses. Simulation tests of the methods, as well as the designed hardware, are also presented in this paper as a contribution to the development researches of horizontal motion control

Evaluation of the possibility of using normalization with cobalt in detection of anthropogenic heavy metals in sediments

Geochemical normalization with conservative elements has been effectively used for assessing the enrichment of metal pollutants and distinguishing their natural and anthropogenic sources. Without correcting for textural and mineralogical variability, a comparison of heavy metal data with regional background is complicated because of large variablity due to irregular grain size and sediment composition. The normalization with cobalt in the enrichment factor calculation presents a new approach in detection of anthropogenic elements in sediments. In present study, the heavy metal concentrations (Cd, Cu, Fe, Mn, Cr, Ni, Pb, V and Zn) were determined in the river sediments of 35 rivers in Serbia. The enrichment factor (EF) was used to estimate the anthropogenic heavy metals input as well as to make a quantification of the metal enrichment degree. Different research sources recommend the use of Fe, Li, Al and Si as conservative elements. Within the scope of this research the cobalt was selected as the element for the normalization. It was observed that the cobalt concentration is not higher than the regional background concentration, which is similar to the average concentration of this element in the continental crust. The positive correlation between Cd, Cr, Fe, Ni, Pb, V, Mn and Zn with Co suggests that it could therefore be a suitable normalizing element in EF calculations for the studied river sediments. The anthropogenic influence of heavy metal pollution could be traced by the use of such EF values, and the values for the studied river systems are presented

Trace element study in Tisa River and Danube alluvial sediment in Serbia

The contaminated sediment serves as a long-term source of toxic elements, since that mobility and transport in the environment of these elements are strongly influenced to associated solid phase. In this study, the modified Tessier sequential extraction procedure was applied for the fractionation of Cd, As, Hg, Cu, Zn, Cr, Pb, Ni and V in the sediments (Tisa River and canal sediments - Danube alluvial formation), to obtain an overall classification of trace element pollution in these areas through its spatial distribution. Investigations of this region are important due to the widespread occurrence of metal mining activities throughout the Tisa and Danube drainage basins and possibilities of contamination with toxic elements at studies localities. Five steps of the sequential extraction procedure partitioned elements into CH3COONH4 extractable (F1), NH2OH center dot HC carbonate extractable and easily reducible (F2), H2C2O4/(NH4)2C2O4 moderately reducible (F3), H2O2-HNO3 organic extractable (F4), and HCl acid soluble residue (F5). Analyses of the extracts were performed by flame atomic absorption spectrometry. To indicate the degree of risk of toxic elements, risk assessment code and contamination factor have been used. The results of partitioning study indicate that more easily mobilized forms (metals in adsorbed/exchangeable/carbonate forms or bound to amorphous Fe and Mn oxyhydroxides and Fe and Mn oxides) were predominant for copper, zinc, cadmium and lead, which can be used as indicators for input from anthropogenic source. In contrast, the largest amount of chromium and nickel were associated with the inert fraction, which reduced their solubility and rendered them immobile under natural conditions and indicative of natural origins. Most of remaining portion of metals was bound to ferromanganese oxides fraction. It is concluded that sequential extraction results proved useful to distinguish between anthropogenic and geochemical sources of elements in the sediments