#trace metals

The goal of this study was to see how dust from a cement plant in northwestern Mekelle affected soil fertility and the shape and yields of three frequently grown crops: wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and teff (Eragrostis tef.). Three top bulky soil samples were taken from three locations: 500 metres (Site-1), 1000 metres (Site-2) and 1500 metres (Site-3) from the western side of a cement industry, where dust is mostly blown by the wind. A fourth control soil sample was taken 6 kilometres distant from the facility in an undamaged region. The soil samples were utilised in a pot experiment at Mekelle University, which took place in a glasshouse. yield and morphological Standard scales were used to measure shoot, root, and spike lengths, as well as leaf area. AAS and UV spectroscopy were used to determine the concentration of main metals: Ca, K, Na, Mg, Mn, and trace elements: Cd, Zn, Cu, Pb, Ni, Cr, and Fe in soil and plant parts, respectively. When compared to the control site, the results demonstrated that dust emissions had a significant impact in raising the trace metals content in the soil and, as a result, the trace metals concentration of crop components. Both clinker feed and clinker, which make up the majority of cement industry dust, had higher Pb, Cu, and Cr levels. With the exception of Cr, the concentrations of the other trace elements (Pb, Cu, and Zn) were lower. Please see the link :- https://www.ikprress.org/index.php/JOGAE/article/view/322

http://www.sciencedaily.com/releases/2014/10/141015084514.htm

Polysulfone (PSF) filter holders have an upper chamber with either a receiver or funnel. Choose from 250- or 500-mL upper chambers and either 250-, 500-, or 1000-mL receivers (all are graduated in 50-mL increments). Holders accept 47- and 50-mm diameter membranes. Supplied with two types of membrane supports. Use the sterilization membrane support for fast flow through; use the analytical support to keep the membrane perfectly flat for the analysis of trapped particles. Receivers with covers are available separately to increase your storage capacity (see table). Transparent PSF is autoclavable, break-resistant, and nontoxic. PSF exhibits low protein binding and contains low levels of trace metals and organic leachables. Use holders for vacuum or pressure filtration up to 10 psig. Thermo Scientific Nalgene Polysulfone Filter Holder; filter holder with funnel; upper chamber cap., All ports accept 1/4" to 5/16" ID pressure tubing. Funnel models have vacuum gaskets to fit filtering flasks. NALGENE.

Trace Metals in the Wester Schelde Estuary: A Case-Study of a Polluted, Partially Anoxic Estuary Oceans and lakes are characterized by large residence times and can thus be considered as being in an equilibrium or quasi-equilibrium state. In contrast, estuaries, which constitute the interface between the fresh water and marine ecosystems, are biogeochemically and physically very dynamic. Strong gradients in physical and chemical variables such as temperature, pH, salinity, dissolved oxygen, nutrients, amount and composition of particulates result from the mixing of fresh water and saline end members. These gradients provoke increased biogeochemical processes, generally resulting in a geochemical filter (the area of high turbidity, showing enhanced adsorption-desorption processes) and a biological filter (the area of high plankton activity showing, besides a high uptake of nutrients, a high accumulation of trace metals). Both filters disturb the conservative mixing pattern of the trace metals in an estuary. In addition, four aspects make the Scheldt estuary very unusual and different from other estuaries: the Scheldt is a tide-governed estuary which means larger residence times; the upper estuary receives large inputs of biodegradable organic matter which leads to oxygen depletion in winter and to anoxic conditions in summer; inputs of toxic pollutants occur in the upper estuary by the industrial park of Antwerp; the anoxic zone, the zone of pollutant input and the zone of the turbidity maximum coincide geographically. The Scheldt estuary is thus an ideal field laboratory for the study of biogeochemical processes which do not occur elsewhere, or only partially, to a very low extent or in a specific compartment, i.e. the sediments. More specifically, redox processes involving trace metals, the formation of non-labile metal complexes, and the methylation of mercury occur as a result of anoxic conditions and the high load of organic matter. Several models describing in detail the transport, the sedimentation and the speciation of the trace metals in this well-mixed estuary (all major estuaries in EC countries adjacent to the North Sea or the Atlantic Ocean are well-mixed) are presented in this book. A comparison of the metal concentrations over a 15-year period shows a net reduction of the pollution level.