The second industrial area located south of Riyadh City – Saudi Arabia was selected for detailed study as pollution of this area with heavy metals has accelerated dramatically during the last decades. The concentrations of eight metals (Cd, Cr, Co, Cu, Fe, Ni, Pb and Zn) in soils and different plant organs of seven native plant species (Calotropis procera , Citrullus colocynthis , Rhazya strict...

To investigate the impact of artisanal zinc smelting activities (AZSA) on the distribution and enrichment of trace metal(loid)s in street dust of a small city in Guizhou province, SW China, street dust samples were collected and analyzed for 10 trace metal(loid)s (Cr, Co, Ni, Cu, Zn, As, Cd, Sb, Pb, and Hg). Meanwhile, the health risks of local resident exposed to street dust were assessed. The...

In this work, the effects of 20 transition element additions on interfacial adhesion energy and electronic structure Al(111)/6H-SiC(0001) interfaces have been studied by first-principles method. For pristine interfaces, both Si-terminated C-terminated covalent bond characteristics. The interface has higher binding energy, which is mainly due to stronger formed larger charge transfer between C A...

A systematic survey of As, Cd, Cr, Cu, Ni, Pb and Zn concentrations in vegetables from 416 samples (involving 100 varieties) in Beijing was carried out for assessing the potential health risk to local inhabitants. The results indicated that the metal concentrations in vegetables ranged from < 0.001 to 0.479 microg/g fresh weight (fw) (As), < 0.001 to 0.101 microg/g fw (Cd), < 0.001 to 1.04 micr...

Toxicity tests were conducted with the marine copepod Acartia tonsa to assess the effects of dietary metal exposure. The diatom Thalassiosira pseudonana was cultured with Ag, Zn, Cu, or Ni and used as diets for adult A. tonsa over a 7-d exposure, and copepod survival and reproduction were measured throughout the exposure period. For all metals, reproduction was the most sensitive endpoint, with...

Factors affecting the transport and retention of Cd, Cr, Cu, Ni, Pb and Zn in acidic groundwaters as they pass through estuarine sediments were investigated using column experiments. Acidic groundwaters caused the rapid dissolution of iron sulfide (AVS) and other iron and manganese phases from sediments that are important for metal binding and buffering. Metal breakthrough to overlying water oc...

Due to rapid industrialization and urbanization lead atmospheric deposition of heavy metals and dust load to become a global problem. We investigated the deposition of dust and heavy metals (Pb, Cd, Ni, Zn, Mn and Cu) at selected urban and sub-urban sites of Varanasi, India. Dustfall samples from different sampling location were collected and selected heavy metals viz. Pb, Cd, Cr, Ni, Zn, Mn an...

Let {Xi} be a sequence of independent, identically distributed random variables with an intermediate regularly varying right tail F̄ . Let (N,C1, C2, . . .) be a nonnegative random vector independent of the {Xi} with N ∈ N ∪ {∞}. We study the weighted random sum SN = ∑Ni=1 CiXi , and its maximum, MN = sup1≤k<N+1 ∑ki=1 CiXi . This type of sum appears in the analysis of stochastic recursions, incl...

2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS); Hg was determined by cold vapor technique. Under the optimum experimental conditions...

The removal of heavy metal from sludge before disposal or application to farmland is a necessary step to achieve a more safe sludge usage or disposal. Chemical extraction using inorganic acids (nitric, hydrochloric) and organic acids (citric, oxalic) were tested for extraction of chromium, copper, nickel, lead and zinc from contaminated sewage sludge at different pH and reaction time. Results r...