In general, the total content of heavy metals and trace elements in soils is useful, but the speciation (bioavailability) is also in need for agricultural purpose, for example. The present paper studies the efficiency of some soil remediation treatments on soils polluted, especially with copper, by using sequential chemical extraction (SCE). Usually, SCE is fractioned, according to Tessier, in five fractions: exchangeable, carbonate bound, Fe and Mn oxide bound, organic matter bound and residual. Copper (Cu) is one of the contaminants found in many soils around the world. In small concentration, it is an essential microelement for plants and organisms, but in high concentrations, it is harmful for the entire ecosystem. Because the concentrations of Cu are associated with soil texture and several other parameters, many remediation soil treatments are based on organic mixture, by converting the element into a less exchangeable form, and thus less bioavailable. In this study, the efficiency of organic amendments such as organic matter (OM), zero-valent iron with organic matter (OMZ), dolomite (DL) and organic matter with dolomite (OMDL) are investigated. These treatments were applied on soils affected by Cu pollution. The results indicated that OMDL and OMZ treatments had the best efficiency on Cu pollution, by enhancing the stability of the element, decreasing the level of bioavailability.
The cooperation between scientists and numismatics is needed because there is a practical requirement to extract all the information from materials in order to accomplish a complete research. In this paper several Romanian coins from early 20 th century are analysed using scanning electron microscopy (SEM) and energy dispersive Xray spectroscopy (EDX) in order to determine the micro-chemical nature and structure in order to establish the conservation state and manufacturing method. The results indicated that the coins were authentic and for some cases mechanical evidences were presented, suggesting pre-heating before minting. Generally, the metallic samples were relatively well protect against the aggressive external factors but, due to the natural corrosion process, many corrosion products were formed on the metallic surface.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.