No abstract

The samples of fruits of the grapevine (Vitis vinifera, cultivar Tamjanika) and the peach tree (Prunus persica L. Batech) from the Bor region were analyzed using an ICP-OES to determine the content of iron (Fe). This was done in order to assess possible health risks related to this essential element; the region of Bor's municipality is known as one of the most polluted areas in Serbia. The content of Fe in unwashed grapes seems not to be affected by the mining/metallurgical activities, as it was either in the normal concentration range or was at even lower than critical deficiency concentration in plants (21.8-98 mg/kg). The level of Fe in the samples of peaches ranged from 62.4 to 1418 mg/kg, which is much higher than that in grape samples and in one case, even higher than the phytotoxic threshold. The values of the enrichment factor (EF) were lower than 2 in the case of grape samples, while for peach samples, these values ranged from rather low (0.99) to extremely high (22.66). Based on the herein obtained results, in the region of Bor, it seems that the cultivation of grapevine should be favored over the cultivation of peach trees.

IZVOD -Da bi se smanjilo zagaĎenje vazduha i ispoštovala zakonska regulative, u izduvne sisteme motornih vozila (putnička, teretna i druga vozila, a u poslednje vreme i graĎevinske i poljoprivredne mašine) ugraĎuju se katalizatori tj. katalitički konvertori. Njihov zadatak je da štetne proizvode sagorevanja tečnih fosilnih goriva prevedu u manje štetne produkte. U katalitičkim konvertorima, rodijum se koristi za redukciju, a platina i paladijum za oksidaciju gasova. U radu su prikazani struktura i princip rada auto katalizatora budući da su automobili najzastupljenija motorna vozila na putevima širom sveta i da se predviĎa da će bar do 2020. godine dominirati proizvodnja automobila sa benzinskim i dizel motorima.Ključne reči: auto katalizatori, struktura, princip rada ABSTRACT -Catalytic converters are incorporated into motor vehicle emission systems (passenger cars, trucks and other motor vehicles, as well as civil and agricultural machines, as of lately) to reduce air pollution as well as to meet the the emission standards.Their purpose is to convert toxic emissions generated by combustion of liquid fossil fuels into less harmful products. In catalytic converters, rhodium is used for the reduction of gasses, whereas platinum and palladium are used for the oxidation of gasses. This paper presents the structure and operating principle of automotive catalysts in view of the fact that cars are the most prevalent motor vehicles worldwide and due to the fact that the production of cars with gasoline and diesel engines will dominate until at least 2020.

IZVOD -U radu je prikazano stanje i perspektive u proizvodnji platinske grupe metala iz primarnih i sekundarnih sirovina, kao i njihova primena. Na osnovu ponude i potražnje za PGM ukazano je na značaj i potrebu za povećanjem stepena reciklaže sekundarnih sirovina. Pokazano je da se najveće količine platinskih metala koriste u proizvodnji auto katalizatora i da je njihova reciklaža jako bitna za očuvanje prirodnih resursa. Reciklaža i održivi razvoj 7 (2014) 9-21Pregledni rad UDK 628.4.037:546.91 UVOD Platinska grupa metala (PGM) obuhvata platinu, paladijum, iridijum, rodijum, osmijum i rutenijum, od kojih je platina najvažnija pa cela grupa nosi naziv "platinski metali". Platinski metali se odlikuju visokim tačkama topljenja, velikom hemijskom otpornošću, većinom su rastegljivi i kovni, grade brojne legure i komplekse [1].Platinski metali spadaju u izrazito retke elemente. U izveštaju Evropske Komisije iz 2010.godine [2], 14 sirovina u Evropi označeno je kao "kritične" na osnovu ekonomskih parametara i dostupnosti istih, u okviru kojih se nalazi i PGM (pored grupe retkih metala,