In this paper we study the influence of substituting one CO ligand in [Fe2(CO)6{μ-(SCH2)2(Ph)P=O}] (1) by better σ-donor L ligands affording [Fe2(CO)5(L){μ-(SCH2)2(Ph)P=O}] {L = PPh3 (2) and P(OEt)3 (3)} in relation to the steric interactions and the voltammetric behavior. Cyclic voltammetric investigations under N2 and CO showed remarkable differences in the electrochemical behaviour of comple...

ten chromite ores from ophiolite complexes in se iran were analyzed mineralogically by xrd, chemically by xrf, and mineral chemistry by epma. the identified paragenesis of silicate minerals of chromite ores with the x-ray diffraction is pronounced differently. it consists of secondary phases formed as serpentine, cr-containing chlorite (kaemmererite), chromic garnet (uarovite) with preserved pa...

Experiments were performed in parallel using six identical UASB (upflow anaerobic sludge blanket) reactors to examine the effects of iron (Fe2+) on sludge granulation during start-up. Introduction of Fe2+ at concentrations of 300 and 450 mg/L enhanced the granulation process in UASB reactors, while dosage of Fe2+ (150 mg/L) had little effect on the sludge granulation. The Fe2+concentration in g...

in this paper, grafting of acrylic acid monomer on gum tragacanth was performed. variable of experiment included concentration of initiators and monomer, time, and temperature. grafting efficiency was measured in the term of percentage of grafting (%g) and percentage of grafting efficiency (%e). effectiveness of grafted gum in ferrous ion removal at different condition was assessed. according t...

The ability of superoxide anion (O2-) from stimulated human neutrophils (PMNs) to release ferrous iron (Fe2+) from transferrin was assessed. At pH 7.4, unstimulated PMNs released minimal amounts of O2- and failed to facilitate the release of Fe2+ from holosaturated transferrin. In contrast, incubation of phorbol myristate acetate (PMA)-stimulated PMNs with holosaturated transferrin at pH 7.4 en...

Reactions of Fe2(CO)6(μ-pdt) (pdt = SCH2CH2CH2S) with aminodiphosphines Ph2PN(R)PPh2 (R = allyl, (i)Pr, (i)Bu, p-tolyl, H) have been carried out under different conditions. At room temperature in MeCN with added Me3NO·2H2O, dibasal chelate complexes Fe2(CO)4{κ(2)-Ph2PN(R)PPh2}(μ-pdt) are formed, while in refluxing toluene bridge isomers Fe2(CO)4{μ-Ph2PN(R)PPh2}(μ-pdt) are the major products. Se...

UNLABELLED Iron and copper toxicity has been presumed to involve the formation of hydroxyl radical (*OH) from H2O2 in the Fenton reaction. The aim of this study was to verify that Fe2+-O2 and Cu+-O2 chemistry is capable of generating *OH in the quasi physiological environment of Krebs-Henseleit buffer (KH), and to compare the ability of the Fe2+-O2 system and of the Fenton system (Fe2+ + H2O2) ...

We hypothesized that exposure of cells to H2O2 plus Fe2+ would increase formation of cell-derived lipid peroxides that would inactivate prostaglandin H synthase, resulting in decreased prostaglandin synthesis. Therefore, we treated human endothelial cells with 0-100 microM H2O2 followed immediately by addition of 0-200 microM Fe2+. After oxidant exposure, cells were stimulated with 20 microM ar...

The N-nitroso-derivative of melatonin, NOM (1-nitrosomelatonin), which has been demonstrated to be a NO* [oxidonitrogen*] donor in buffered solutions, is a new potential drug particularly in neurological diseases. The advantage of NOM, a very lipophilic drug, is its ability to release both melatonin and NO*, an easily diffusible free radical. In order to evaluate the distribution and the pharma...

Duodenal Fe2+ uptake is essential to body Fe2+ homeostasis, but the interaction of metals with the uptake process remains unclear. The present study compared the effects of four essential trace metals (Mn2+, Zn2+, Co2+ and Ni2+) with two toxic metals (Pb2+ and Cd2+) on Fe2+ uptake across the brush border membrane of villus-attached duodenal enterocytes. Everted rat duodenum was exposed to buffe...