heavy metal contamination around the national iranian lead and zinc company (nilz) in zanjan province was evaluated in this paper. collected data were used to appraise the degree of soil contamination and also the source of pollution in the study area based on geoaccumulation index (igeo), and enrichment factor (ef). the levels of fe, zn, cd and pb in the samples exceed those reported in litera...

Background: Unsafe food consumption is a severe problem because of heavy metal contamination, which is caused by director indirect activities of industries. The present study was conducted to assess the risk of human health by Heavy metals (Cu, Co, Fe, Zn and Mn) through the intake of vegetables and fishes obtained from the area adjacent to the Hazaribag tannery campus, Dhaka, Bangladesh. Resul...

1. Sheep fitted with a rumen fistula and either a re-entrant cannula at the proximal duodenum or a re-entrant cannula at the terminal ileum were given twice daily 480-520 g dry matter as fresh perennial ryegrass, or white or red clover. Flows of digesta were corrected to 100% recovery of chronic oxide. 2. The quantities (g/24 h) of zince and cobalt leaving the stomach were significantly greater...

The magnetic circular dichroism of the d-d transitions of Co(I1) when substituted for Zn(I1) in the Zn(II)-Cu(I1) enzyme bovine superoxide dismutase enzyme is reported. Magnetic circular dkhroism of the Co(I1) chromophore in the Co(II)-Cu(I1) enzyme is typical of tetrahedral Co(I1) compounds. The magnetic circular dichroism band pattern is almost identical with the magnetic circular dichroism o...

Zeolites containing Zn in their frameworks are promising materials for ion-exchange and catalysis because of their unique ion-exchange capabilities and characteristic Lewis acidity. However, expensive organic compounds often required in their synthesis can prevent their practical uses. Here, a facile organic-free synthesis route for new zincoaluminosilicate zeolites having MOR topology, in whic...

Metal ions in metallo-β-lactamases (MBLs) play a major role in catalysis. In this study we investigated the role of the metal ions in the Zn1 and Zn2 sites of MBL L1 during catalysis. A ZnCo (with Zn(II) in the invariant Zn1 site and Co(II) in the Zn2 site) analog of MBL L1 was prepared by using a biological incorporation method. Extended X-ray Absorption Fine Structure (EXAFS) spectroscopic st...

Concentrations of the environmentally sensitive elements (ESEs) As, Co, Cu, Mn, Ni, Pb, V and Zn in smaller than 100 μm street dust particles from Xining were measured using X-ray fluorescence spectrometry and their contamination levels were assessed based on enrichment factor (EF), geoaccumulation index (Igeo) and pollution load index (PLI). The concentrations of As, Co, Cu, Mn, Ni, Pb, V and ...

Palladium zinc aluminium (2.28/10.37/0.35), Pd(2.28(1))Zn(10.37(1))Al(0.35(1)), represents the upper limit of Al substitution into the parent cubic γ-brass Pd(2+x)Zn(11-x). The structure can be described in terms of a 26-atom cluster consisting of an inner tetra-hedron (IT), an outer tetra-hedron (OT), an octa-hedron (OH) and a cubocta-hedron (CO), with the substituted Al atoms partially occupy...

Superoxide dismutase (SOD) is a very important reactive oxygen species (ROS)-scavenging enzyme. In this study, the functions of a Cu/Zn SOD gene (SaCu/Zn SOD), from Sedum alfredii, a cadmium (Cd)/zinc/lead co-hyperaccumulator of the Crassulaceae, was characterized. The expression of SaCu/Zn SOD was induced by Cd stress. Compared with wild-type (WT) plants, overexpression of SaCu/Zn SOD gene in ...