To make jewellery of gold, gold is alloyed with other metals. It is of great importance to accurately determine the total amount of pure gold in alloys used for making the jewellery and in jewellery made of gold, because it determines its value on the market. Several analytical methods are used for this purpose. This study was based on comparison of results of analysis of gold alloy for 14-carat jewellery obtained by non-destructive fluorescent analysis method and destructive cupellation method. The null hypothesis with 95 % confidence level on equivalence in measurement precision of perecnt by percent mass of gold in three very similar gold alloy samples in reproducibility conditions (three measurement series) for standard cupellation method and the method compared (validated), XRF method, has been confirmed. F-test did not confirm null hypothesis on precision equivalence for two mentioned analysis methods. There is a significant difference in variance values. However, the t-test was carried out, which verified the null hypothesis on equivalence between mean values of results achieved in two compared values. In order to confirm applicabilty of two methods ,Zscore was calculated giving values of less than 2, using statistical data from inter-laboratory program with 62 participating laboratories applying cupellation method, and 60 laboratories applying XRF method for analysis of gold alloy used in production of 14-carat jewellery. Article info Received: 06/12/2011 Accepted: 25/01/2012
U posljednje vrijeme postoje razne kalkulacije o streljivu koje koristi osiromašeni uranij, a koje je upotrebljavano tijekom rata u Bosni i Hercegovini (1992.–1995.). Pored toga, podruèje Bosne i Hercegovine bilo je pod izravnim utjecajem globalnih disperzijskih procesa u razdoblju mjeseca svibnja 1986. godine, kao posljedica emisije iz Nuklearne elektrane “Lenin” u Èernobilu. Cilj istraÞivanja bio je odrediti specifiènu radioaktivnost: 238U, 226Ra, 210Pb, 232Th, 40K i 137Cs u površinski uzetim uzorcima tla u gradu Sarajevu i njegovoj okolici. Uzorci tla uzeti su s devet lokaliteta u gradu Sarajevu i njegovoj okolici. Upotrebljavan je detektor Ge HP spojen na Ortec MCA Gamma Vision 32 Software kao i instrumentna neutronska aktivacijska tehnika (INAA).
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