الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Conclusion
REEs exhibit similar chemical and physical properties. REE and their isotopes have important uses and applications in different fields. The accurate and precise analysis of REEs at a wide range of concentrations is a vital consideration in all types and phases of studies. The determination of REEs in geological samples is extremely important because they are the source materials of all REE products and because REE data provide a unique insight into chemical behavior of natural systems. The isotope ratios measurements by ICP-MS are important for quite different applications. Accordingly, the scientists became also interested in REE isotopes methods of analyses.
Several rock samples were selected from the Precambrian rocks of Egypt. Each sample was divided into two portions. One portion, from which REEs were separated by different techniques of ion exchange resins, was analyzed by ICP-MS in Egypt. The other portion was analyzed in a well-reputed Canadian laboratory. The obtained data from the two labs were then compared.
REEs separated by cation- or anion–exchange resins yielded data that show significant deviation from the data obtained on the same samples from Canada. Separation of REEs using mixed cation - anion exchange resins yielded better results (more precise). Even significantly better results were obtained on REEs separated using mixed anion-cation exchange resins. The best results (closest to data of the reference samples) are obtained on samples analyzed without any REEs separation. The comparisons are based on the analytical results obtained on eight granite rock samples and four reference geological samples