The detection limit for the analytical conditions employed was 0.004 ng g - 1. The accuracy and precision of the procedure were evaluated by analysis of the certified reference material SARM-7 (South Africa Bureau of Standards) and W- 1 (USGS). The procedure consisted of thermal neutron irradiation of about 500 mg of the sample, followed by sintering with sodium peroxide, precipitation with tellurium and high resolution gamma-ray spectrometry with a hyper-pure Ge detector. In the present paper, a radiochemical neutron activation method for the determination of iridium in geological materials is presented. The determination of very low amounts of iridium is particularly important on account of some anomalous concentrations of iridium in sedimentary rock samples, related to the impact of an extraterrestrial object responsible for extinctions at the Cretaceous-Tertiary (K-T) boundary. The determination of PGE has attracted great interest due not only to the increasing utilization of these elements in modern industry, but also to the information that these elements can provide on mantle processes. The analysis of the platinum group elements (PGE: Ru, Rh, Pd, Os, Ir and Pt) in geological materials is difficult, due to the low concentrations of these elements ( ng g - 1 or sub ng g - 1 ) and their heterogeneous distribution in many geological matrices. International Nuclear Information System (INIS) On the basis of the results obtained, the optimal parameters of the new system components were defined.ĭetermination of iridium at low levels (sub ng g- 1) in geological materials by neutron activation analysis The aim was to analyze the impact of the most important parameters of the components that are needed for new network elements, on the performance of these coexistent networks. Analysis of Coexisting GPON and NG-PON 1 (10 G-PON Systemsĭirectory of Open Access Journals (Sweden)įull Text Available In this paper, the simulation model of coexisting GPON and NG-PON 1 (10 G-PON systems is presented, which has been developed for the analysis of feasibility and implementation issues of this coexistence.
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