An evaluation of Hg, Cr and heavy metals pollution in seawater and sediments of Durres Bay Adriatic Sea-Albania

An evaluation of different state of Hg, Cr and heavy metals pollution in seawater and sediments of Durres Bay, Adriatic Sea is git en. Some geological considerations and normalisation procedures are used to explain the anthropogenic-input fraction of heavy metals in this bay. It is dearly demonstrated that some industrial actil ities, such as mining, harbouring and chemical plant activity, notably affect Cr$^{+6}$ and heasw metals concentration in sediments. It is demonstrated that the most important pollutant of Durres Bay is chromium, whose concentration in sediments goes to 550 mg/kg and the highest concentration of Cr$^{+6}$ was found to be 16.6 $\mu$g/L in seawater near the ex-chemical factory.
Keywords: AAS, heavy metals, seawater, sediments, background levels, normalisation

Experimental Examination of the Na, K, Ca, Sr and Mg Effects in the Aes Determination of Li in the Underground Brines

In this paper the effects of Na, K, Ca, Sr and Mg on the atomic emission signal of Li were studied. Three types of interferences were observed: band emission of Sr and Ca compounds, scattering of the lithium radiation from the high concentrated ions, and the interference of ionization. The experimental examination of these interferences was carried out using both classic univariate and factorial design methods. The results of both methods are similar. However, it has been demonstrated that an experimental design based on factorial analysis is a significantly more powerful and economical approach.Ach-Models in Chemistr

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