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This work highlights the potential for the synthesis of new PtSnZn catalysts with enhanced efficiency and durability for methanol oxidation reaction (MOR) in low-temperature fuel cells. In this research, PtZn and PtSnZn nanoparticles deposited on high surface area Vulcan XC-72R Carbon support were c …

This is a preliminary study of the depth distribution of 137Cs radionuclides in cultivated anthrosol soil of a 15-year old peach tree plantation at the experimental field “Radmilovac” near Belgrade. Before planting, the soil was ploughed at the depth of 1 m. The soil had not been annually ploughed, irrigated and treated with mineral fertilizers for three years before sampling. Activity concentration for 137Cs ranged from 1.8 Bq kg-1 to 35 Bq kg-1. Along the soil depth it varied highly, reaching as high a total variation coefficient as 83 %. Radiocaesium distribution patterns depended on the extent of soil mixing in the plough layer, as it was mechanically transferred from the surface to the lower soil layers during cultivation. 137Cs was associated with humus content and fixation to clay fractions in the soil. Our results single out soil’s hygroscopic water as a valuable parameter for 137Cs behaviour that could be used commonly if the measurement is standardised., Ovo je preliminarno istraživanje dubinske raspodjele radionuklida 137Cs u kultiviranome zemljištu tipa Antrosol 15 godina starog voćnjaka pod zasadom breskvi koje pripada oglednom poljoprivrednom dobru “Radmilovac” u blizini Beograda. Dubokim oranjem do dubine od 1 m zemljište je pripremljeno za postavljanje zasada breskvi. Tri godine prije uzorkovanja zemljišta prekinuta je obrada voćnjaka odnosno godišnje oranje (do 40 cm dubine), navodnjavanje i unos mineralnoga gnojiva. Koncentracija aktivnosti 137Cs kretala se od 1,8 Bq kg-1 do 35 Bq kg-1 i bitno varirala s povećanjem dubine zemljišta te dostigla ukupni koeficijent varijacije od 83 %. Obrasci raspodjele radiocezija po dubini zavisili su od stupnja obrade zemljišta u prethodnom razdoblju, s obzirom na to da je mehanička manipulacija zemljišta dovela do njegove prisutnosti i u nižim slojevima. 137Cs izravno je korelirao sa sadržajem humusa i bio je fiksiran za glinovitu frakciju zemljišta, što upućuje na njegovu povezanost s česticama zemlje. Unatoč tome što se sadržaj higroskopske vlage u zemljištu pokazao korisnim parametrom za opis ponašanja cezija, za njezino određivanje još uvijek nije utvrđena standardna metoda mjerenja.