In this study we examine the impact of dissolved metal concentrations on the parameters that are commonly determined from complexometric titrations in seawater. We use the non-ideal competitive adsorption (NICA) model within the framework of the chemical speciation program visual MINTEQ with iron as a model metal. We demonstrate that dissolved iron concentrations effect the determined parameter...

This research describes the development of a dual preservationand field-speciation technique for As(III) and As(V) speciation of a sample preserved with ethylenediaminetetraacetic acid (EDTA) and acetic acid (HAc). The new method was compared with existing preservationand field-speciation methods and was shown to be accurate and precise in spite of possible interference from ferrous iron in the...

A flow-injection determination method was proposed for the speciation of reactive species of iron in non-acidified water samples. Iron was determined by the spectrophotometric monitoring of the iron-catalyzed oxidation of o-phenylenediamine with hydrogen peroxide. The reactive iron was characterized as Fe3+ and Fe(III)Li(3-in), where i = 1 or 2 for a unidentate ligand and i = 1 for a bidentate ...

Atmospheric inputs of iron to the open ocean are hypothesized to modulate ocean biogeochemistry. This review presents an integration of available observations of atmospheric iron and iron deposition, and also covers bioavailable iron distributions. Methods for estimating temporal variability in ocean deposition over the recent past are reviewed. Desert dust iron is estimated to represent 95% of...

Slag-containing pastes and concretes were analysed by element-specific synchrotron-based techniques to determine the speciation of iron on crushed materials through spatially resolved micro-spectroscopic studies. The investigated cement samples hydrated either in laboratory, or exposed river sea water. Metallic iron, along with minor proportions sulphide magnetite was detected laboratory sample...

In a high mountain lake and catchment area, a natural process of phosphorus enrichment is observed, induced by the iron-cycle. Investigations focus on the speciation of P and Fe in iron and manganese rich oxidic mineral crusts formed at the surface of rock pebbles. Iron and phosphorus are spatially associated although they are not forming iron phosphate minerals. While Fe and P K edge XAS spect...

Iron metallodrugs comprise mineral supplements, anti-hypertensive agents and, more recently, magnetic nanomaterials, with both therapeutic and diagnostic roles. As biologically-active metal compounds, concern has been raised regarding the impact of these compounds when emitted to the environment and associated ecotoxicological effects for the fauna. In this work we assessed the relative stabili...

Iron chlorosis is a very common nutritional disorder in plants that can be treated using iron fertilizers. Synthetic chelates have been used to correct this problem, but nowadays environmental concerns have enforced the search for new, more environmentally friendly ligands, such as lignosulfonates. In this paper, Fe coordination environment and speciation in lignosulfonate (LS) complexes prepar...