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Ovo tehničko rešenje predstavlja prenosni uređaj za indikativno merenje kvaliteta vazduha. U osnovnoj varijanti uređaj omogućuje merenje: koncentracije suspendovanih čestica (frakcije PM10 i PM2.5) u vazduhu, temperature i relativne vlažnosti vazduha. U proširenoj varijanti ovaj uređaj, pored navedenih parametara, može da se koristi za indikativna merenja koncentracija ugljen-dioksida u vazduhu, koncentracija lako isparljvih organskih materija (formaldehid, toluen) u vazduhu, i vazdušnog pritiska. Uređaj se zasniva na Arduino Mega 2560 i Arduino Uno mikrokontrolerskim pločama i jeftinim (low-cost) senzorima.

Research on chalcopyrite leaching represents a great challenge, given its importance as one of the most abundant copper minerals and its significant role in global copper extraction. This study aimed to evaluate the effects of different parameters on chalcopyrite leaching by hydrogen peroxide as a strong oxidizing reagent in sulfuric acid solution. A series of leaching tests were carried out to investigate the effect of the solid/liquid ratio, stirring speed, temperature, oxidant and acid concentrations, and lixiviant dosing method on copper extraction from chalcopyrite concentrate. The catalytic decomposition of hydrogen peroxide occurred in the investigated leaching system, as reflected in the obtained metal extraction values. Copper extraction was increased in the first 60 min of the reaction, after which it essentially ceased. The maximum final copper extraction of 64.5% was attained with 3.0 mol/L H2O2 in 3.0 mol/L H2SO4 at a temperature of 40 °C after 120 min of reaction. Due to the catalytic decomposition of hydrogen peroxide in the examined leaching system, the leaching experiment was performed with the periodic addition of lixiviant at specific time intervals as well. The dissolution process was described by the first-order kinetics equation with an apparent activation energy of ~39 kJ/mol. Finally, XRD and SEM-EDS analyses were used to characterize the leached residue, and the results showed that the formation of elemental sulfur on the chalcopyrite surface affected the dissolution process.

Palladium alloys with low nickel content are commonly used as catalyst-trap for platinum or platinum-rhodium catalysts in the process of production of nitric acid. Pure palladium and, consequently, alloys with a high concentration of Pd are highly resistant in many corrosion environments across the full pH range, from 0 to 14 and beyond, in the presence of different anions. Mineral acids do not affect palladium, especially at lower concentrations; they can be dissolved just in the mix of them. However, nickel in the alloy can be selectively dissolved in single mineral acid with the use of an oxidation agent or anodic polarization, which is the more controllable process. The aim of the work is the research of dealloying of PdNi5 in 0.5M sulfuric acid under anodic polarization conditions. This study used open circuit potential, linear polarization resistance, and chronoamperometry as electrochemical methods. Scanning electronic microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) and inductively coupled plasma mass spectrometry (ICP-MS) were used as structural and analytical techniques for the study of PdNi5 alloy dealloying in 0.5M sulfuric acid at three different anodic potentials., Legure paladijuma sa niskim sadržajem nikla se obično koriste kao havatači katalizatora za platinu ili platina-rodijum katalizatore u procesu proizvodnje azotne kiseline. Čisti paladijum i posledično legure sa visokom koncentracijom Pd su visoko otporni u mnogim korozionim sredinama u punom pH opsegu, od 0 do 14 i više, u prisustvu različitih anjona. Mineralne kiseline ne utiču na paladijum, posebno na nižim koncentracijama; može se rastvoriti samo u njihovoj mešavini. Međutim, nikl u leguri može se selektivno rastvoriti u jednoj mineralnoj kiselini uz upotrebu oksidacionog agensa ili anodne polarizacije, što je proces koji se može više kontrolisati. Cilj rada je istraživanje dealloying-a PdNi5 u 0,5M sumpornoj kiselini u uslovima anodne polarizacije. Ova studija je koristila potencijal otvorenog kola, otpor linearne polarizacije i hronoamperometriju kao elektrohemijske metode. Skenirajuća elektronska mikroskopija sa energetski disperzivnom rendgenskom spektroskopijom (SEM-EDS) i masena spektrometrija induktivno spregnute plazme (ICP-MS) korišćene su kao strukturne i analitičke tehnike za proučavanje dealloying-a legure PdNi5 u 0,5M sumpornoj kiselini na tri različita anodna potencijala.

Binary palladium alloys with nickel are known to have catalytic activity and are also used as catalyst-trap in the synthesis of nitric acid. High Pd alloys are corrosive resistant in many solutions, including highly alkaline and highly acidic. Although generally not prone to corrosion in low concentrations of mineral acids due to the high content of palladium in it, this alloy is still prone to the dealloying effect under specific conditions. The dealloying process was researched under anodic polarization in 1.0M nitric acid solution. Scanning electronic microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and electrochemical methods were used to study the susceptibility of PdNi5 alloy to dealloying.

U ovoj disertaciji ispitan je hemijski sastav i oksidativni potencijal (OP) dve frakcije respirabilnih čestica (PM2.5 i PM10), u različitim sredinama. Za utvrĎivanje sezonskih promena, prvo istraţivanje sprovedeno je u urbanoj (UB) i urbano-industrijskoj (UI) sredini tokom leta i zime. Kako bi se ispitale promene OP-a tokom dana, drugo istraţivanje sprovedeno je u urbanoj sredini pod uticajem saobraćaja. Rezultati prvog istraţivanja ukazuju da su prosečne koncentracije obe ispitivane frakcije čestica, u UB i UI, bile vrlo slične tokom leta. Tokom zime, u UB koncentracije PM2.5 bile su tri puta više, a PM10 dvostruko više u odnosu na koncentracije izmerene u UI. U obe ispitivane sredine, tokom obe sezone, PM2.5/PM10 odnos bio je visok, što ukazuje na značajan udeo finih čestica u gruboj frakciji, koje prvenstveno imaju antropogeno poreklo. Dominantnu vrstu u obe frakcije čestica, kao i u obe ispitivane sredine, činila je organska materija, čiji je procenat varirao u zavisnosti od godišnjeg doba. Prosečni OC/EC odnosi, kao i koncentracije WSOC-a, u obe frakcije čestica, bili su značajno viši tokom zimskog perioda u UB, što je posledica prisustva velike količine sekundarnih organskih aerosola. Prosečne koncentracije jonskih vrsta i 22 kvantifikovana elementa, tokom obe sezone, bile su više u UI. Primenom DTT i DCFH eseja, u obe ispitivane sredine, više vrednosti OP-a utvrĎene su za PM2.5, a primenjeni eseji pokazali su suprotne trendove. U obe ispitivane sredine, primenom DTT eseja, OP vrednosti bile su više tokom letnjeg perioda, dok su DCFH esejom više vrednosti utvrĎene tokom zime. U drugom istraţivanju, najveća količina ROS-ova izmerena je oko 14 h, što moţe biti posledica maksimalne količine saobraćaja ili velikog doprinosa SOA. Umerena, statistički značajna korelacija utvrĎena je izmeĎu BPEAnit i DCFH eseja, što ukazuje na veću toksičnost koja potiče od organskih vrsta prisutnih u vazduhu. Kombinovanjem rezultata više eseja preciznije je utvrĎen kvalitet vazduha, In this dissertation, the chemical content and oxidative potential (OP) of two fractions of respirable particles (PM2.5 and PM10) were examined in different еnvironments. The first study was conducted in urban (UB) and urban-industrial (UI) environments during summer and winter to determine the seasonal changes. The second study was conducted in an urban environment influenced by the traffic to examine the differences in OP during the day. The results of the first study indicate that the average concentrations of both analyzed particle fractions, in UB and UI, were very similar during the summer. During the winter, PM2.5 levels in UB were three times higher and PM10 twice as high as in UI level. In both examined environments, during both seasons, the PM2.5/ PM10 ratio was high, which indicates a significant contribution of fine particles in the coarse fraction, which are primarily of anthropogenic origin. In both examined environments, the dominant particle fraction was the organic matter, the percentage of which varied depending on the season. Average OC/EC ratios, as well as WSOC concentrations, in both particle fractions, were significantly higher during the winter period in UB, due to the presence of a large amount of secondary organic aerosols. The average concentrations of ion species and 22 quantified elements, during both seasons, were higher in the UI. Using DTT and DCFH assays, in both examined environments, higher OP values were determined for PM2.5, and the applied assays showed opposite trends. In both urban environments, using DTT assays, OP values were higher during the summer period, while DCFH assays were higher values determined during the winter. In another study, the largest amount of ROS was measured around 2 p.m., which may be due to maximum traffic or a significant contribution from SOA. A moderate, statistically significant correlation was found between BPEAnit and DCFH assays, indicating higher toxicity derived from organic species present i

U ovoj disertaciji ispitan je hemijski sastav i oksidativni potencijal (OP) dve frakcije respirabilnih čestica (PM2.5 i PM10), u različitim sredinama. Za utvrĎivanje sezonskih promena, prvo istraţivanje sprovedeno je u urbanoj (UB) i urbano-industrijskoj (UI) sredini tokom leta i zime. Kako bi se ispitale promene OP-a tokom dana, drugo istraţivanje sprovedeno je u urbanoj sredini pod uticajem saobraćaja. Rezultati prvog istraţivanja ukazuju da su prosečne koncentracije obe ispitivane frakcije čestica, u UB i UI, bile vrlo slične tokom leta. Tokom zime, u UB koncentracije PM2.5 bile su tri puta više, a PM10 dvostruko više u odnosu na koncentracije izmerene u UI. U obe ispitivane sredine, tokom obe sezone, PM2.5/PM10 odnos bio je visok, što ukazuje na značajan udeo finih čestica u gruboj frakciji, koje prvenstveno imaju antropogeno poreklo. Dominantnu vrstu u obe frakcije čestica, kao i u obe ispitivane sredine, činila je organska materija, čiji je procenat varirao u zavisnosti od godišnjeg doba. Prosečni OC/EC odnosi, kao i koncentracije WSOC-a, u obe frakcije čestica, bili su značajno viši tokom zimskog perioda u UB, što je posledica prisustva velike količine sekundarnih organskih aerosola. Prosečne koncentracije jonskih vrsta i 22 kvantifikovana elementa, tokom obe sezone, bile su više u UI. Primenom DTT i DCFH eseja, u obe ispitivane sredine, više vrednosti OP-a utvrĎene su za PM2.5, a primenjeni eseji pokazali su suprotne trendove. U obe ispitivane sredine, primenom DTT eseja, OP vrednosti bile su više tokom letnjeg perioda, dok su DCFH esejom više vrednosti utvrĎene tokom zime. U drugom istraţivanju, najveća količina ROS-ova izmerena je oko 14 h, što moţe biti posledica maksimalne količine saobraćaja ili velikog doprinosa SOA. Umerena, statistički značajna korelacija utvrĎena je izmeĎu BPEAnit i DCFH eseja, što ukazuje na veću toksičnost koja potiče od organskih vrsta prisutnih u vazduhu. Kombinovanjem rezultata više eseja preciznije je utvrĎen kvalitet vazduha, In this dissertation, the chemical content and oxidative potential (OP) of two fractions of respirable particles (PM2.5 and PM10) were examined in different еnvironments. The first study was conducted in urban (UB) and urban-industrial (UI) environments during summer and winter to determine the seasonal changes. The second study was conducted in an urban environment influenced by the traffic to examine the differences in OP during the day. The results of the first study indicate that the average concentrations of both analyzed particle fractions, in UB and UI, were very similar during the summer. During the winter, PM2.5 levels in UB were three times higher and PM10 twice as high as in UI level. In both examined environments, during both seasons, the PM2.5/ PM10 ratio was high, which indicates a significant contribution of fine particles in the coarse fraction, which are primarily of anthropogenic origin. In both examined environments, the dominant particle fraction was the organic matter, the percentage of which varied depending on the season. Average OC/EC ratios, as well as WSOC concentrations, in both particle fractions, were significantly higher during the winter period in UB, due to the presence of a large amount of secondary organic aerosols. The average concentrations of ion species and 22 quantified elements, during both seasons, were higher in the UI. Using DTT and DCFH assays, in both examined environments, higher OP values were determined for PM2.5, and the applied assays showed opposite trends. In both urban environments, using DTT assays, OP values were higher during the summer period, while DCFH assays were higher values determined during the winter. In another study, the largest amount of ROS was measured around 2 p.m., which may be due to maximum traffic or a significant contribution from SOA. A moderate, statistically significant correlation was found between BPEAnit and DCFH assays, indicating higher toxicity derived from organic species present i

Urban airborne particles contain a wide spectrum of components, known to have harmful effects on human health. This study reports a detailed investigation of fine particulate matter (PM2.5), chemical content and oxidative potential derived from two different urban environments. During summer and winter, 20-day campaigns were conducted at Belgrade city center (urban-background site – UB) and Bor (urban-industrial site – UI). Using various analytical techniques, carbonaceous compounds, water-soluble inorganic ions, major and trace elements were determined, while the oxidative potential of PM2.5 was estimated by dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay (OPDCFH values). The mean PM2.5 concentrations in both urban environments were above the recommended daily value, and the dominant PM2.5 mass contributor was organic matter (29–55%). The OC/EC ratio was significantly higher at UB site during winter, which was an indication of a considerable contribution of secondary organic carbon to the overall organic carbon (OC). Water-soluble organic carbon (WSOC) was also higher at UB than at UI site, and it probably came from the same sources as OC. In general, the different partition of secondary organic aerosol (SOA) in warm and cold periods affected the number of organic components. Sulfates and nitrates were the most abundant ions at both sites and they counted approximately 40% (summer) and 50% (winter) of total ions. Further, the concentrations of the most elements, particularly some potentially carcinogenic elements such as As, Cd and Pb were significantly higher at UI, due to the emissions from the copper smelter complex in the vicinity. The mean OPDCFH values were similar during the summer at both sampling sites, whereas a statistically significant difference between sites was noticed in favor of UB environment in winter.

This study reports the contents and sources of Cu, Hg, Cr, Ni, Co, Zn, Pb, Cd, As, and B pollution in soil samples from Srem in the province of Vojvodina (Republic of Serbia). They are collected in the vicinity of local industrial facilities. The main objective of this study is evaluating the impact of the industrial facilities on the eventual contamination of soils used mostly for agricultural manufacturing. This paper describes the implementation of the combination of methods to estimate the ecological status and determine potential ecological risk. This study applies sequential extraction, pollution indices, comparison with the guidelines, and statistical analysis. Other soil parameters, such as organic matter content, pH, and clay content were measured to evaluate their influence on the trace element content. The investigated soil samples exhibited the raised contents of Ni, Hg, and Cu. Elevated contents of toxic elements observed in localities accommodated within an impact zone affected by industrial complexes, indicating a correlation between the contamination of surrounding soil and potential impact on plants. The most mobile elements are Hg, Cd, and B, while Cr is the least mobile and potential least bioavailable. The results indicate Cr and Ni content increase marking the presence of bedrock, notably in the area of underlying ultramafic rocks and the surface zones influenced by diluvial-proluvial and alluvial processes. The second source of Cr and Ni in the soils of Srem is industrial activities such as leather, cement industry, as well as the metal processing factory.

Fokus ove studije je na biometrijsku klasifikaciju biljaka, biljnih organa, lokaliteta i vremena uzorkovanja, u smislu praćenja stepena usvajanja toksičanih (As, Cd, Hg i Pb) i esencijalnih elemenata (Cu i Zn), i mogućnost primene u fito-remedijaciji. Stepen usvajanja elemenata zavisi od biljne vrste i njenih morfoloških i fizioloških osobina. Usvajanje toksičnih i esencijalnih elemenata u ovom radu je praćeno kod tri vrste biljaka (podbel, maslačak i kopriva). Uzorkovanje biljaka i zemljišta je vršeno u priobalnom regionu Kriveljske reke, Srbija. Analiza glavnih komponenti i analiza varijanse su korišćene za procenu efekasnosti usvajanja toksičnih i esencijalnih elemenata kod pomenutih biljnih vrsta, biljnih organa (korena, stabla i lišća), lokaliteta i vremena uzorkovanja (april, maj, jun). Dobijeni rezultati su pokazali da je razlika u usvajanju toksičnih i esencijalnih elemenata najviše zavisi od sorte i tipova biljnih organa. Biometrijske tehnike pružaju mogućnost za bolje razumevanje ponašanja biljaka i dobijanja mnogo korisnih informacija iz izvornih podataka., The focus of this study is on the biometric classification of plants, plant organs, sampling sites and sampling time, in terms of toxic (As, Cd, Hg and Pb) and essential elements (Cu and Zn) monitoring, and possible the application in phyto-remediation. The degree of adoption of elements depends on the plant species and its morphological and physiological properties, therefore the adoption of toxic and essential elements in three plant species (coltsfoot, dandelion and nettles) was investigated. Vegetation experiments were carried out in the coastal region of river Kriveljska, Serbia. Principal component analysis and analysis of variance were used for assessing the effect of plant types, plant organs (root, shoot and leaves), and sampling sites and sampling time (April, May, June) on toxic and essential elements uptake. Obtained results showed that a difference in toxic and essential elements uptake depends mostly upon the cultivar and the plant organ types. Biometric techniques provided a good opportunity for a better understanding the behaviour of plants and obtaining much more useful information from the original data.

U radu je analizirano ukupno 416 uzoraka frakcija respirabilnih čestica (PM10 i PM2.5),sakupljenih tokom 2009. i 2010. godine sa lokaliteta obdaništa "Boško Buha" u Borukoje se nalazi u neposrednoj blizini industrijskog kompleksa za proizvodnju bakra,Rudarsko-topioničarskog basena Bor. Uzorkivači su postavljeni i unutar obdaništa, ispolja, radi prikupljanja podataka o kvalitetu kako vazduha u spoljašnjoj sredini tako iunutrašnjem prostoru, radi analiziranja uticaja zagađenja iz spoljašnje sredine kao idetektovanja eventualno prisutnih izvora zagađenja u unutrašnjm prostoru..., In this study, the total of 416 samples of respirable particles (PM10 and PM2.5)collected during 2009 and 2010 from the kindergarten Bosko Buha in Bor, located inthe vicinity of Copper Smelter Complex RTB, were analyzed. Samplers were placedindoor and outdoor in order to collect the data about air quality, both indoor andoutdoor, to analyzed the influence of ambient air to the indoor pollution and to detect apossible sources of indoor pollution...

U radu je analizirano ukupno 416 uzoraka frakcija respirabilnih čestica (PM10 i PM2.5), sakupljenih tokom 2009. i 2010. godine sa lokaliteta obdaništa "Boško Buha" u Boru koje se nalazi u neposrednoj blizini industrijskog kompleksa za proizvodnju bakra, Rudarsko-topioničarskog basena Bor. Uzorkivači su postavljeni i unutar obdaništa, i spolja, radi prikupljanja podataka o kvalitetu kako vazduha u spoljašnjoj sredini tako i unutrašnjem prostoru, radi analiziranja uticaja zagađenja iz spoljašnje sredine kao i detektovanja eventualno prisutnih izvora zagađenja u unutrašnjm prostoru..., In this study, the total of 416 samples of respirable particles (PM10 and PM2.5) collected during 2009 and 2010 from the kindergarten Bosko Buha in Bor, located in the vicinity of Copper Smelter Complex RTB, were analyzed. Samplers were placed indoor and outdoor in order to collect the data about air quality, both indoor and outdoor, to analyzed the influence of ambient air to the indoor pollution and to detect a possible sources of indoor pollution...

Mass concentrations of particulate matter (PM) fractions were measured in educational buildings in the city of Nis, Serbia. Two sampling campaigns were conducted in winter periods. The first campaign was in the period from 21 February to 15 April 2010 at the Faculty of Occupational Safety (FOS) and the second campaign was from 20 March to 4 April 2013 at the primary school Void Karadorde (VK). PM measurements were carried out with low volume samplers Sven/Leckel LVS3. The average daily PM10 concentration inside the FOS (47.0 +/- 21.8 mu g/m(3)) was lower than PM10 concentration in outdoor air (50.7 +/- 28.1 mu g/m(3)). The average daily PM10 concentration inside the VK (54.6 +/- 17.6 mu g/m(3)) was higher than in outdoor air (47.9 +/- 22.8 mu g/m(3)). The 24-hours, average PM10 concentrations at FOS exceeded the EU limit value (50 mu g/m(3)) during 34% of days outdoors and 39% of days indoors. The 24-hours average PM10 concentrations at VK exceeded the limit value during 35% of days outdoors and 53% of days indoors. The 24-hours average PM2.5 concentrations at VK exceeded the WHO daily mean guideline value (25 mu g/m(3)) during 71% of days outdoors and 88% of days indoors. The average PM10 I/O ratio at VK was 1.57 during teaching hours, and 1.00 during no teaching hours. Similarly, average PM2.5 I/O ratio at VK was 1.11 during teaching hours and 0.90 during no teaching hours. Average daily PM2.5/PM10 ratio in the ambient air at VK was 0.87 and 0.82 at FOS. Very strong correlations between the indoor and outdoor PM concentrations were observed at VK during no teaching hours (r gt 0.8). Moderate to strong negative correlations were found between the wind speed and PM at both schools. High outdoor PM concentrations and resuspension of particles are possible reasons for the elevated indoor PM concentrations found in the study., U radu su prikazani rezultati merenja suspendovanih čestica frakcija PM10 i PM2.5 u dve izabrane obrazovne ustanove u Nišu. Kampanje merenja sprovedene su u zimskom periodu. Prva u periodu od 21.02. do 15.04.2010. na Fakultetu zaštite na radu (FOS), a druga u periodu od 20.03. do 04.04.2013. u osnovnoj školi Vožd Karađorđe (VK). Uzorkovanje suspendovanih čestica vršeno je uzorkivačima Sven/Leckel LVS3, simultano, unutar i izvan odabranih ustanova. Prosečna dnevna koncentracija čestica PM10 unutar objekta FOS (47,0±21,8 μg/m3) bila je niža u odnosu na prosečnu dnevnu koncentraciju PM10 u ambijentalnom vazduhu (50,7±28,1 μg/m3). Prosečna dnevna koncentracija čestica PM10 unutar objekta VK (54.6±17.6 μg/m3) bila je viša u odnosu na prosečnu dnevnu koncentraciju PM10 u ambijentalnom vazduhu (47.9±22.8 μg/m3). Srednje dnevne koncentracije čestica PM10 izmerene na lokaciji FOS u ambijentalnom vazduhu prelazile su dnevnu graničnu vrednost (50 ìg/m3) tokom 34% dana trajanja kampanje merenja. Srednje dnevne koncentracije čestica PM10 izmerene unutar objekta FOS prelazile su dnevnu graničnu vrednost tokom 39% dana trajanja kampanje merenja. Srednje dnevne koncentracije čestica PM10 izmerene na lokaciji VK u ambijentalnom vazduhu prelazile su dnevnu graničnu vrednost tokom 35% dana trajanja kampanje merenja, odnosno tokom 53% dana trajanja kampanje u unutrašnjosti objekta VK. Srednje dnevne koncentracije čestica PM2,5 izmerene na lokaciji VK u ambijentalnom vazduhu prelazile su dnevnu graničnu vrednost (25 ìg/m3) tokom 71% dana trajanja kampanje, odnosno tokom 88% dana u unutrašnjosti objekta VK. Prosečan dnevni odnos unutra/spolja čestica frakcije PM10 na lokaciji VK iznosio je 1,57 u vreme nastave, odnosno 1,00 kada nije bilo nastave. Prosečan dnevni odnos unutra/spolja čestica frakcije PM2,5 na lokaciji VK iznosio je 1.11 u vreme nastave, odnosno 0.90 kada nije bilo nastave. Prosečan dnevni odnos PM2,5/PM10 u ambijentalnom vazduhu na lokaciji VK bio je 0,87, odnosno 0,82 na